Macintosh resource fork data: Java parsing library

The data format of Macintosh resource forks, used on Classic Mac OS and Mac OS X/macOS to store additional structured data along with a file's main data (the data fork). The kinds of data stored in resource forks include:

  • Document resources: images, sounds, etc. used by a document
  • Application resources: graphics, GUI layouts, localizable strings, and even code used by an application, a library, or system files
  • Common metadata: custom icons and version metadata that could be displayed by the Finder
  • Application-specific metadata: because resource forks follow a common format, other applications can store new metadata in them, even if the original application does not recognize or understand it

Macintosh file systems (MFS, HFS, HFS+, APFS) support resource forks natively, which allows storing resources along with any file. Non-Macintosh file systems and protocols have little or no support for resource forks, so the resource fork data must be stored in some other way when using such file systems or protocols. Various file formats and tools exist for this purpose, such as BinHex, MacBinary, AppleSingle, AppleDouble, or QuickTime RezWack. In some cases, resource forks are stored as plain data in separate files with a .rsrc extension, even on Mac systems that natively support resource forks.

On modern Mac OS X/macOS systems, resource forks are used far less commonly than on classic Mac OS systems, because of compatibility issues with other systems and historical limitations in the format. Modern macOS APIs and libraries do not use resource forks, and the legacy Carbon API that still used them has been deprecated since OS X 10.8. Despite this, even current macOS systems still use resource forks for certain purposes, such as custom file icons.

Application

Mac OS

File extension

["rsrc", "dfont"]

KS implementation details

License: MIT
Minimal Kaitai Struct required: 0.9

References

This page hosts a formal specification of Macintosh resource fork data using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.

Usage

Runtime library

All parsing code for Java generated by Kaitai Struct depends on the Java runtime library. You have to install it before you can parse data.

The Java runtime library is published in the Maven Central Repository. Refer to the artifact page for instructions how to add it into your project with the build tool that you use.

Code

Parse a local file and get structure in memory:

ResourceFork data = ResourceFork.fromFile("path/to/local/file.["rsrc", "dfont"]");

Or parse structure from a byte array:

byte[] someArray = new byte[] { ... };
ResourceFork data = new ResourceFork(new ByteBufferKaitaiStream(someArray));

After that, one can get various attributes from the structure by invoking getter methods like:

data.header() // => The resource file's header information.
data.dataBlocksWithIo() // => Use `data_blocks` instead,
unless you need access to this instance's `_io`.

Java source code to parse Macintosh resource fork data

ResourceFork.java

// This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild

import io.kaitai.struct.ByteBufferKaitaiStream;
import io.kaitai.struct.KaitaiStruct;
import io.kaitai.struct.KaitaiStream;
import java.io.IOException;
import java.util.ArrayList;


/**
 * The data format of Macintosh resource forks,
 * used on Classic Mac OS and Mac OS X/macOS to store additional structured data along with a file's main data (the data fork).
 * The kinds of data stored in resource forks include:
 * 
 * * Document resources:
 *   images, sounds, etc. used by a document
 * * Application resources:
 *   graphics, GUI layouts, localizable strings,
 *   and even code used by an application, a library, or system files
 * * Common metadata:
 *   custom icons and version metadata that could be displayed by the Finder
 * * Application-specific metadata:
 *   because resource forks follow a common format,
 *   other applications can store new metadata in them,
 *   even if the original application does not recognize or understand it
 * 
 * Macintosh file systems (MFS, HFS, HFS+, APFS) support resource forks natively,
 * which allows storing resources along with any file.
 * Non-Macintosh file systems and protocols have little or no support for resource forks,
 * so the resource fork data must be stored in some other way when using such file systems or protocols.
 * Various file formats and tools exist for this purpose,
 * such as BinHex, MacBinary, AppleSingle, AppleDouble, or QuickTime RezWack.
 * In some cases,
 * resource forks are stored as plain data in separate files with a .rsrc extension,
 * even on Mac systems that natively support resource forks.
 * 
 * On modern Mac OS X/macOS systems,
 * resource forks are used far less commonly than on classic Mac OS systems,
 * because of compatibility issues with other systems and historical limitations in the format.
 * Modern macOS APIs and libraries do not use resource forks,
 * and the legacy Carbon API that still used them has been deprecated since OS X 10.8.
 * Despite this,
 * even current macOS systems still use resource forks for certain purposes,
 * such as custom file icons.
 * @see <a href="https://developer.apple.com/library/archive/documentation/mac/pdf/MoreMacintoshToolbox.pdf#page=151">Inside Macintosh, More Macintosh Toolbox, Resource Manager, Resource Manager Reference, Resource File Format</a>
 * @see <a href="http://www.pagetable.com/?p=50">Inside Macintosh, Volume I, The Resource Manager, Format of a Resource File</a>
 * @see <a href="https://github.com/kreativekorp/ksfl/wiki/Macintosh-Resource-File-Format">Source</a>
 * @see <a href="https://github.com/dgelessus/mac_file_format_docs/blob/master/README.md#resource-forks">Source</a>
 */
public class ResourceFork extends KaitaiStruct {
    public static ResourceFork fromFile(String fileName) throws IOException {
        return new ResourceFork(new ByteBufferKaitaiStream(fileName));
    }

    public ResourceFork(KaitaiStream _io) {
        this(_io, null, null);
    }

    public ResourceFork(KaitaiStream _io, KaitaiStruct _parent) {
        this(_io, _parent, null);
    }

    public ResourceFork(KaitaiStream _io, KaitaiStruct _parent, ResourceFork _root) {
        super(_io);
        this._parent = _parent;
        this._root = _root == null ? this : _root;
        _read();
    }
    private void _read() {
        this.header = new FileHeader(this._io, this, _root);
        this.systemData = this._io.readBytes(112);
        this.applicationData = this._io.readBytes(128);
    }

    /**
     * Resource file header,
     * containing the offsets and lengths of the resource data area and resource map.
     */
    public static class FileHeader extends KaitaiStruct {
        public static FileHeader fromFile(String fileName) throws IOException {
            return new FileHeader(new ByteBufferKaitaiStream(fileName));
        }

        public FileHeader(KaitaiStream _io) {
            this(_io, null, null);
        }

        public FileHeader(KaitaiStream _io, KaitaiStruct _parent) {
            this(_io, _parent, null);
        }

        public FileHeader(KaitaiStream _io, KaitaiStruct _parent, ResourceFork _root) {
            super(_io);
            this._parent = _parent;
            this._root = _root;
            _read();
        }
        private void _read() {
            this.ofsDataBlocks = this._io.readU4be();
            this.ofsResourceMap = this._io.readU4be();
            this.lenDataBlocks = this._io.readU4be();
            this.lenResourceMap = this._io.readU4be();
        }
        private long ofsDataBlocks;
        private long ofsResourceMap;
        private long lenDataBlocks;
        private long lenResourceMap;
        private ResourceFork _root;
        private KaitaiStruct _parent;

        /**
         * Offset of the resource data area,
         * from the start of the resource file.
         * 
         * In practice,
         * this should always be `256`,
         * i. e. the resource data area should directly follow the application-specific data area.
         */
        public long ofsDataBlocks() { return ofsDataBlocks; }

        /**
         * Offset of the resource map,
         * from the start of the resource file.
         * 
         * In practice,
         * this should always be `ofs_data_blocks + len_data_blocks`,
         * i. e. the resource map should directly follow the resource data area.
         */
        public long ofsResourceMap() { return ofsResourceMap; }

        /**
         * Length of the resource data area.
         */
        public long lenDataBlocks() { return lenDataBlocks; }

        /**
         * Length of the resource map.
         * 
         * In practice,
         * this should always be `_root._io.size - ofs_resource_map`,
         * i. e. the resource map should extend to the end of the resource file.
         */
        public long lenResourceMap() { return lenResourceMap; }
        public ResourceFork _root() { return _root; }
        public KaitaiStruct _parent() { return _parent; }
    }

    /**
     * A resource data block,
     * as stored in the resource data area.
     * 
     * Each data block stores the data contained in a resource,
     * along with its length.
     */
    public static class DataBlock extends KaitaiStruct {
        public static DataBlock fromFile(String fileName) throws IOException {
            return new DataBlock(new ByteBufferKaitaiStream(fileName));
        }

        public DataBlock(KaitaiStream _io) {
            this(_io, null, null);
        }

        public DataBlock(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList.Reference _parent) {
            this(_io, _parent, null);
        }

        public DataBlock(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList.Reference _parent, ResourceFork _root) {
            super(_io);
            this._parent = _parent;
            this._root = _root;
            _read();
        }
        private void _read() {
            this.lenData = this._io.readU4be();
            this.data = this._io.readBytes(lenData());
        }
        private long lenData;
        private byte[] data;
        private ResourceFork _root;
        private ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList.Reference _parent;

        /**
         * The length of the resource data stored in this block.
         */
        public long lenData() { return lenData; }

        /**
         * The data stored in this block.
         */
        public byte[] data() { return data; }
        public ResourceFork _root() { return _root; }
        public ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList.Reference _parent() { return _parent; }
    }

    /**
     * Resource map,
     * containing information about the resources in the file and where they are located in the data area.
     */
    public static class ResourceMap extends KaitaiStruct {
        public static ResourceMap fromFile(String fileName) throws IOException {
            return new ResourceMap(new ByteBufferKaitaiStream(fileName));
        }

        public ResourceMap(KaitaiStream _io) {
            this(_io, null, null);
        }

        public ResourceMap(KaitaiStream _io, ResourceFork _parent) {
            this(_io, _parent, null);
        }

        public ResourceMap(KaitaiStream _io, ResourceFork _parent, ResourceFork _root) {
            super(_io);
            this._parent = _parent;
            this._root = _root;
            _read();
        }
        private void _read() {
            this.reservedFileHeaderCopy = new FileHeader(this._io, this, _root);
            this.reservedNextResourceMapHandle = this._io.readU4be();
            this.reservedFileReferenceNumber = this._io.readU2be();
            this._raw_fileAttributes = this._io.readBytes(2);
            KaitaiStream _io__raw_fileAttributes = new ByteBufferKaitaiStream(_raw_fileAttributes);
            this.fileAttributes = new FileAttributes(_io__raw_fileAttributes, this, _root);
            this.ofsTypeList = this._io.readU2be();
            this.ofsNames = this._io.readU2be();
        }

        /**
         * A resource file's attributes,
         * as stored in the resource map.
         * 
         * These attributes are sometimes also referred to as resource map attributes,
         * because of where they are stored in the file.
         */
        public static class FileAttributes extends KaitaiStruct {
            public static FileAttributes fromFile(String fileName) throws IOException {
                return new FileAttributes(new ByteBufferKaitaiStream(fileName));
            }

            public FileAttributes(KaitaiStream _io) {
                this(_io, null, null);
            }

            public FileAttributes(KaitaiStream _io, ResourceFork.ResourceMap _parent) {
                this(_io, _parent, null);
            }

            public FileAttributes(KaitaiStream _io, ResourceFork.ResourceMap _parent, ResourceFork _root) {
                super(_io);
                this._parent = _parent;
                this._root = _root;
                _read();
            }
            private void _read() {
                this.resourcesLocked = this._io.readBitsIntBe(1) != 0;
                this.reserved0 = this._io.readBitsIntBe(6);
                this.printerDriverMultifinderCompatible = this._io.readBitsIntBe(1) != 0;
                this.noWriteChanges = this._io.readBitsIntBe(1) != 0;
                this.needsCompact = this._io.readBitsIntBe(1) != 0;
                this.mapNeedsWrite = this._io.readBitsIntBe(1) != 0;
                this.reserved1 = this._io.readBitsIntBe(5);
            }
            private Integer asInt;

            /**
             * The attributes as a packed integer,
             * as they are stored in the file.
             */
            public Integer asInt() {
                if (this.asInt != null)
                    return this.asInt;
                long _pos = this._io.pos();
                this._io.seek(0);
                this.asInt = this._io.readU2be();
                this._io.seek(_pos);
                return this.asInt;
            }
            private boolean resourcesLocked;
            private long reserved0;
            private boolean printerDriverMultifinderCompatible;
            private boolean noWriteChanges;
            private boolean needsCompact;
            private boolean mapNeedsWrite;
            private long reserved1;
            private ResourceFork _root;
            private ResourceFork.ResourceMap _parent;

            /**
             * TODO What does this attribute actually do,
             * and how is it different from `read_only`?
             * 
             * This attribute is undocumented and not defined in <CarbonCore/Resources.h>,
             * but ResEdit has a checkbox called "Resources Locked" for this attribute.
             */
            public boolean resourcesLocked() { return resourcesLocked; }

            /**
             * These attributes have no known usage or meaning and should always be zero.
             */
            public long reserved0() { return reserved0; }

            /**
             * Indicates that this printer driver is compatible with MultiFinder,
             * i. e. can be used simultaneously by multiple applications.
             * This attribute is only meant to be set on printer driver resource forks.
             * 
             * This attribute is not documented in Inside Macintosh and is not defined in <CarbonCore/Resources.h>.
             * It is documented in technote PR510,
             * and ResEdit has a checkbox called "Printer Driver MultiFinder Compatible" for this attribute.
             * @see <a href="https://developer.apple.com/library/archive/technotes/pr/pr_510.html">Apple Technical Note PR510 - Printer Driver Q&As, section '"Printer driver is MultiFinder compatible" bit'</a>
             */
            public boolean printerDriverMultifinderCompatible() { return printerDriverMultifinderCompatible; }

            /**
             * Indicates that the Resource Manager should not write any changes from memory into the resource file.
             * Any modification operations requested by the application will return successfully,
             * but will not actually update the resource file.
             * 
             * TODO Is this attribute supposed to be set on disk or only in memory?
             */
            public boolean noWriteChanges() { return noWriteChanges; }

            /**
             * Indicates that the resource file should be compacted the next time it is written by the Resource Manager.
             * This attribute is only meant to be set in memory;
             * it is cleared when the resource file is written to disk.
             * 
             * This attribute is mainly used internally by the Resource Manager,
             * but may also be set manually by the application.
             */
            public boolean needsCompact() { return needsCompact; }

            /**
             * Indicates that the resource map has been changed in memory and should be written to the resource file on the next update.
             * This attribute is only meant to be set in memory;
             * it is cleared when the resource file is written to disk.
             * 
             * This attribute is mainly used internally by the Resource Manager,
             * but may also be set manually by the application.
             */
            public boolean mapNeedsWrite() { return mapNeedsWrite; }

            /**
             * These attributes have no known usage or meaning and should always be zero.
             */
            public long reserved1() { return reserved1; }
            public ResourceFork _root() { return _root; }
            public ResourceFork.ResourceMap _parent() { return _parent; }
        }

        /**
         * Resource type list and storage area for resource reference lists in the resource map.
         * 
         * The two parts are combined into a single type here for technical reasons:
         * the start of the resource reference list area is not stored explicitly in the file,
         * instead it always starts directly after the resource type list.
         * The simplest way to implement this is by placing both types into a single `seq`.
         */
        public static class TypeListAndReferenceLists extends KaitaiStruct {
            public static TypeListAndReferenceLists fromFile(String fileName) throws IOException {
                return new TypeListAndReferenceLists(new ByteBufferKaitaiStream(fileName));
            }

            public TypeListAndReferenceLists(KaitaiStream _io) {
                this(_io, null, null);
            }

            public TypeListAndReferenceLists(KaitaiStream _io, ResourceFork.ResourceMap _parent) {
                this(_io, _parent, null);
            }

            public TypeListAndReferenceLists(KaitaiStream _io, ResourceFork.ResourceMap _parent, ResourceFork _root) {
                super(_io);
                this._parent = _parent;
                this._root = _root;
                _read();
            }
            private void _read() {
                this.typeList = new TypeList(this._io, this, _root);
                this.referenceLists = this._io.readBytesFull();
            }

            /**
             * Resource type list in the resource map.
             */
            public static class TypeList extends KaitaiStruct {
                public static TypeList fromFile(String fileName) throws IOException {
                    return new TypeList(new ByteBufferKaitaiStream(fileName));
                }

                public TypeList(KaitaiStream _io) {
                    this(_io, null, null);
                }

                public TypeList(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists _parent) {
                    this(_io, _parent, null);
                }

                public TypeList(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists _parent, ResourceFork _root) {
                    super(_io);
                    this._parent = _parent;
                    this._root = _root;
                    _read();
                }
                private void _read() {
                    this.numTypesM1 = this._io.readU2be();
                    entries = new ArrayList<TypeListEntry>(((Number) (numTypes())).intValue());
                    for (int i = 0; i < numTypes(); i++) {
                        this.entries.add(new TypeListEntry(this._io, this, _root));
                    }
                }

                /**
                 * A single entry in the resource type list.
                 * 
                 * Each entry corresponds to exactly one resource reference list.
                 */
                public static class TypeListEntry extends KaitaiStruct {
                    public static TypeListEntry fromFile(String fileName) throws IOException {
                        return new TypeListEntry(new ByteBufferKaitaiStream(fileName));
                    }

                    public TypeListEntry(KaitaiStream _io) {
                        this(_io, null, null);
                    }

                    public TypeListEntry(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists.TypeList _parent) {
                        this(_io, _parent, null);
                    }

                    public TypeListEntry(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists.TypeList _parent, ResourceFork _root) {
                        super(_io);
                        this._parent = _parent;
                        this._root = _root;
                        _read();
                    }
                    private void _read() {
                        this.type = this._io.readBytes(4);
                        this.numReferencesM1 = this._io.readU2be();
                        this.ofsReferenceList = this._io.readU2be();
                    }
                    private Integer numReferences;

                    /**
                     * The number of resources in the reference list for this type.
                     */
                    public Integer numReferences() {
                        if (this.numReferences != null)
                            return this.numReferences;
                        int _tmp = (int) (KaitaiStream.mod((numReferencesM1() + 1), 65536));
                        this.numReferences = _tmp;
                        return this.numReferences;
                    }
                    private ReferenceList referenceList;

                    /**
                     * The resource reference list for this resource type.
                     */
                    public ReferenceList referenceList() {
                        if (this.referenceList != null)
                            return this.referenceList;
                        KaitaiStream io = _parent()._parent()._io();
                        long _pos = io.pos();
                        io.seek(ofsReferenceList());
                        this.referenceList = new ReferenceList(io, this, _root, numReferences());
                        io.seek(_pos);
                        return this.referenceList;
                    }
                    private byte[] type;
                    private int numReferencesM1;
                    private int ofsReferenceList;
                    private ResourceFork _root;
                    private ResourceFork.ResourceMap.TypeListAndReferenceLists.TypeList _parent;

                    /**
                     * The four-character type code of the resources in the reference list.
                     */
                    public byte[] type() { return type; }

                    /**
                     * The number of resources in the reference list for this type,
                     * minus one.
                     * 
                     * Empty reference lists should never exist.
                     */
                    public int numReferencesM1() { return numReferencesM1; }

                    /**
                     * Offset of the resource reference list for this resource type,
                     * from the start of the resource type list.
                     * 
                     * Although the offset is relative to the start of the type list,
                     * it should never point into the type list itself,
                     * but into the reference list storage area that directly follows it.
                     * That is,
                     * it should always be at least `_parent._sizeof`.
                     */
                    public int ofsReferenceList() { return ofsReferenceList; }
                    public ResourceFork _root() { return _root; }
                    public ResourceFork.ResourceMap.TypeListAndReferenceLists.TypeList _parent() { return _parent; }
                }
                private Integer numTypes;

                /**
                 * The number of resource types in this list.
                 */
                public Integer numTypes() {
                    if (this.numTypes != null)
                        return this.numTypes;
                    int _tmp = (int) (KaitaiStream.mod((numTypesM1() + 1), 65536));
                    this.numTypes = _tmp;
                    return this.numTypes;
                }
                private int numTypesM1;
                private ArrayList<TypeListEntry> entries;
                private ResourceFork _root;
                private ResourceFork.ResourceMap.TypeListAndReferenceLists _parent;

                /**
                 * The number of resource types in this list,
                 * minus one.
                 * 
                 * If the resource list is empty,
                 * the value of this field is `0xffff`,
                 * i. e. `-1` truncated to a 16-bit unsigned integer.
                 */
                public int numTypesM1() { return numTypesM1; }

                /**
                 * Entries in the resource type list.
                 */
                public ArrayList<TypeListEntry> entries() { return entries; }
                public ResourceFork _root() { return _root; }
                public ResourceFork.ResourceMap.TypeListAndReferenceLists _parent() { return _parent; }
            }

            /**
             * A resource reference list,
             * as stored in the reference list area.
             * 
             * Each reference list has exactly one matching entry in the resource type list,
             * and describes all resources of a single type in the file.
             */
            public static class ReferenceList extends KaitaiStruct {

                public ReferenceList(KaitaiStream _io, int numReferences) {
                    this(_io, null, null, numReferences);
                }

                public ReferenceList(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists.TypeList.TypeListEntry _parent, int numReferences) {
                    this(_io, _parent, null, numReferences);
                }

                public ReferenceList(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists.TypeList.TypeListEntry _parent, ResourceFork _root, int numReferences) {
                    super(_io);
                    this._parent = _parent;
                    this._root = _root;
                    this.numReferences = numReferences;
                    _read();
                }
                private void _read() {
                    references = new ArrayList<Reference>(((Number) (numReferences())).intValue());
                    for (int i = 0; i < numReferences(); i++) {
                        this.references.add(new Reference(this._io, this, _root));
                    }
                }

                /**
                 * A single resource reference in a resource reference list.
                 */
                public static class Reference extends KaitaiStruct {
                    public static Reference fromFile(String fileName) throws IOException {
                        return new Reference(new ByteBufferKaitaiStream(fileName));
                    }

                    public Reference(KaitaiStream _io) {
                        this(_io, null, null);
                    }

                    public Reference(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList _parent) {
                        this(_io, _parent, null);
                    }

                    public Reference(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList _parent, ResourceFork _root) {
                        super(_io);
                        this._parent = _parent;
                        this._root = _root;
                        _read();
                    }
                    private void _read() {
                        this.id = this._io.readS2be();
                        this.ofsName = this._io.readU2be();
                        this._raw_attributes = this._io.readBytes(1);
                        KaitaiStream _io__raw_attributes = new ByteBufferKaitaiStream(_raw_attributes);
                        this.attributes = new Attributes(_io__raw_attributes, this, _root);
                        this.ofsDataBlock = this._io.readBitsIntBe(24);
                        this._io.alignToByte();
                        this.reservedHandle = this._io.readU4be();
                    }

                    /**
                     * A resource's attributes,
                     * as stored in a resource reference.
                     */
                    public static class Attributes extends KaitaiStruct {
                        public static Attributes fromFile(String fileName) throws IOException {
                            return new Attributes(new ByteBufferKaitaiStream(fileName));
                        }

                        public Attributes(KaitaiStream _io) {
                            this(_io, null, null);
                        }

                        public Attributes(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList.Reference _parent) {
                            this(_io, _parent, null);
                        }

                        public Attributes(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList.Reference _parent, ResourceFork _root) {
                            super(_io);
                            this._parent = _parent;
                            this._root = _root;
                            _read();
                        }
                        private void _read() {
                            this.systemReference = this._io.readBitsIntBe(1) != 0;
                            this.loadIntoSystemHeap = this._io.readBitsIntBe(1) != 0;
                            this.purgeable = this._io.readBitsIntBe(1) != 0;
                            this.locked = this._io.readBitsIntBe(1) != 0;
                            this.protected = this._io.readBitsIntBe(1) != 0;
                            this.preload = this._io.readBitsIntBe(1) != 0;
                            this.needsWrite = this._io.readBitsIntBe(1) != 0;
                            this.compressed = this._io.readBitsIntBe(1) != 0;
                        }
                        private Integer asInt;

                        /**
                         * The attributes as a packed integer,
                         * as they are stored in the file.
                         */
                        public Integer asInt() {
                            if (this.asInt != null)
                                return this.asInt;
                            long _pos = this._io.pos();
                            this._io.seek(0);
                            this.asInt = this._io.readU1();
                            this._io.seek(_pos);
                            return this.asInt;
                        }
                        private boolean systemReference;
                        private boolean loadIntoSystemHeap;
                        private boolean purgeable;
                        private boolean locked;
                        private boolean protected;
                        private boolean preload;
                        private boolean needsWrite;
                        private boolean compressed;
                        private ResourceFork _root;
                        private ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList.Reference _parent;

                        /**
                         * Indicates that this resource reference is a system reference rather than a regular local reference.
                         * This attribute is nearly undocumented.
                         * For all practical purposes,
                         * it should be considered reserved and should always be zero.
                         * 
                         * This attribute was last documented in the Promotional Edition of Inside Macintosh,
                         * in the Resource Manager chapter,
                         * on pages 37-41,
                         * in a "System References" section that calls itself "of historical interest only".
                         * The final versions of Inside Macintosh only mention this attribute as "reserved for use by the Resource Manager".
                         * <CarbonCore/Resources.h> contains a `resSysRefBit` constant,
                         * but no corresponding `resSysRef` constant like for all other resource attributes.
                         * 
                         * According to the Inside Macintosh Promotional Edition,
                         * a system reference was effectively an alias pointing to a resource stored in the system file,
                         * possibly with a different ID and name (but not type) than the system reference.
                         * If this attribute is set,
                         * `ofs_data_block` is ignored and should be zero,
                         * and `reserved_handle` contains
                         * (in its high and low two bytes, respectively)
                         * the ID and name offset of the real system resource that this system reference points to.
                         * 
                         * TODO Do any publicly available Mac OS versions support system references,
                         * and do any real files/applications use them?
                         * So far the answer seems to be no,
                         * but I would like to be proven wrong!
                         */
                        public boolean systemReference() { return systemReference; }

                        /**
                         * Indicates that this resource should be loaded into the system heap if possible,
                         * rather than the application heap.
                         * 
                         * This attribute is only meant to be used by Mac OS itself,
                         * for System and Finder resources,
                         * and not by normal applications.
                         * 
                         * This attribute may be set both in memory and on disk,
                         * but it only has any meaning while the resource file is loaded into memory.
                         */
                        public boolean loadIntoSystemHeap() { return loadIntoSystemHeap; }

                        /**
                         * Indicates that this resource's data should be purgeable by the Mac OS Memory Manager.
                         * This allows the resource data to be purged from memory if space is needed on the heap.
                         * Purged resources can later be reloaded from disk if their data is needed again.
                         * 
                         * If the `locked` attribute is set,
                         * this attribute has no effect
                         * (i. e. locked resources are never purgeable).
                         * 
                         * This attribute may be set both in memory and on disk,
                         * but it only has any meaning while the resource file is loaded into memory.
                         */
                        public boolean purgeable() { return purgeable; }

                        /**
                         * Indicates that this resource's data should be locked to the Mac OS Memory Manager.
                         * This prevents the resource data from being moved when the heap is compacted.
                         * 
                         * This attribute may be set both in memory and on disk,
                         * but it only has any meaning while the resource file is loaded into memory.
                         */
                        public boolean locked() { return locked; }

                        /**
                         * Indicates that this resource should be protected (i. e. unmodifiable) in memory.
                         * This prevents the application from using the Resource Manager to change the resource's data or metadata,
                         * or delete it.
                         * The only exception are the resource's attributes,
                         * which can always be changed,
                         * even for protected resources.
                         * This allows protected resources to be unprotected again by the application.
                         * 
                         * This attribute may be set both in memory and on disk,
                         * but it only has any meaning while the resource file is loaded into memory.
                         */
                        public boolean protected() { return protected; }

                        /**
                         * Indicates that this resource's data should be immediately loaded into memory when the resource file is opened.
                         * 
                         * This attribute may be set both in memory and on disk,
                         * but it only has any meaning when the resource file is first opened.
                         */
                        public boolean preload() { return preload; }

                        /**
                         * Indicates that this resource's data has been changed in memory and should be written to the resource file on the next update.
                         * This attribute is only meant to be set in memory;
                         * it is cleared when the resource file is written to disk.
                         * 
                         * This attribute is used internally by the Resource Manager and should not be set manually by the application.
                         */
                        public boolean needsWrite() { return needsWrite; }

                        /**
                         * Indicates that this resource's data is compressed.
                         * Compressed resource data is decompressed transparently by the Resource Manager when reading.
                         * 
                         * For a detailed description of the structure of compressed resources as they are stored in the file,
                         * see the compressed_resource.ksy spec.
                         */
                        public boolean compressed() { return compressed; }
                        public ResourceFork _root() { return _root; }
                        public ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList.Reference _parent() { return _parent; }
                    }
                    private Name name;

                    /**
                     * The name (if any) of the resource described by this reference.
                     */
                    public Name name() {
                        if (this.name != null)
                            return this.name;
                        if (ofsName() != 65535) {
                            KaitaiStream io = _root.resourceMap().namesWithIo()._io();
                            long _pos = io.pos();
                            io.seek(ofsName());
                            this.name = new Name(io, this, _root);
                            io.seek(_pos);
                        }
                        return this.name;
                    }
                    private DataBlock dataBlock;

                    /**
                     * The data block containing the data for the resource described by this reference.
                     */
                    public DataBlock dataBlock() {
                        if (this.dataBlock != null)
                            return this.dataBlock;
                        KaitaiStream io = _root.dataBlocksWithIo()._io();
                        long _pos = io.pos();
                        io.seek(ofsDataBlock());
                        this.dataBlock = new DataBlock(io, this, _root);
                        io.seek(_pos);
                        return this.dataBlock;
                    }
                    private short id;
                    private int ofsName;
                    private Attributes attributes;
                    private long ofsDataBlock;
                    private long reservedHandle;
                    private ResourceFork _root;
                    private ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList _parent;
                    private byte[] _raw_attributes;

                    /**
                     * ID of the resource described by this reference.
                     */
                    public short id() { return id; }

                    /**
                     * Offset of the name for the resource described by this reference,
                     * from the start of the resource name area.
                     * 
                     * If the resource has no name,
                     * the value of this field is `0xffff`
                     * i. e. `-1` truncated to a 16-bit unsigned integer.
                     */
                    public int ofsName() { return ofsName; }

                    /**
                     * Attributes of the resource described by this reference.
                     */
                    public Attributes attributes() { return attributes; }

                    /**
                     * Offset of the data block for the resource described by this reference,
                     * from the start of the resource data area.
                     */
                    public long ofsDataBlock() { return ofsDataBlock; }

                    /**
                     * Reserved space for the resource's handle in memory.
                     */
                    public long reservedHandle() { return reservedHandle; }
                    public ResourceFork _root() { return _root; }
                    public ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList _parent() { return _parent; }
                    public byte[] _raw_attributes() { return _raw_attributes; }
                }
                private ArrayList<Reference> references;
                private int numReferences;
                private ResourceFork _root;
                private ResourceFork.ResourceMap.TypeListAndReferenceLists.TypeList.TypeListEntry _parent;

                /**
                 * The resource references in this reference list.
                 */
                public ArrayList<Reference> references() { return references; }

                /**
                 * The number of references in this resource reference list.
                 * 
                 * This information needs to be passed in as a parameter,
                 * because it is stored in the reference list's type list entry,
                 * and not in the reference list itself.
                 */
                public int numReferences() { return numReferences; }
                public ResourceFork _root() { return _root; }
                public ResourceFork.ResourceMap.TypeListAndReferenceLists.TypeList.TypeListEntry _parent() { return _parent; }
            }
            private TypeList typeList;
            private byte[] referenceLists;
            private ResourceFork _root;
            private ResourceFork.ResourceMap _parent;

            /**
             * The resource map's resource type list.
             */
            public TypeList typeList() { return typeList; }

            /**
             * Storage area for the resource map's resource reference lists.
             * 
             * According to Inside Macintosh,
             * the reference lists are stored contiguously,
             * in the same order as their corresponding resource type list entries.
             */
            public byte[] referenceLists() { return referenceLists; }
            public ResourceFork _root() { return _root; }
            public ResourceFork.ResourceMap _parent() { return _parent; }
        }

        /**
         * A resource name,
         * as stored in the resource name storage area in the resource map.
         * 
         * The resource names are not required to appear in any particular order.
         * There may be unused space between and around resource names,
         * but in practice they are often contiguous.
         */
        public static class Name extends KaitaiStruct {
            public static Name fromFile(String fileName) throws IOException {
                return new Name(new ByteBufferKaitaiStream(fileName));
            }

            public Name(KaitaiStream _io) {
                this(_io, null, null);
            }

            public Name(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList.Reference _parent) {
                this(_io, _parent, null);
            }

            public Name(KaitaiStream _io, ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList.Reference _parent, ResourceFork _root) {
                super(_io);
                this._parent = _parent;
                this._root = _root;
                _read();
            }
            private void _read() {
                this.lenValue = this._io.readU1();
                this.value = this._io.readBytes(lenValue());
            }
            private int lenValue;
            private byte[] value;
            private ResourceFork _root;
            private ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList.Reference _parent;

            /**
             * The length of the resource name, in bytes.
             */
            public int lenValue() { return lenValue; }

            /**
             * The resource name.
             * 
             * This field is exposed as a byte array,
             * because there is no universal encoding for resource names.
             * Most Classic Mac software does not deal with encodings explicitly and instead assumes that all strings,
             * including resource names,
             * use the system encoding,
             * which varies depending on the system language.
             * This means that resource names can use different encodings depending on what system language they were created with.
             * 
             * Many resource names are plain ASCII,
             * meaning that the encoding often does not matter
             * (because all Mac OS encodings are ASCII-compatible).
             * For non-ASCII resource names,
             * the most common encoding is perhaps MacRoman
             * (used for English and other Western languages),
             * but other encodings are also sometimes used,
             * especially for software in non-Western languages.
             * 
             * There is no requirement that all names in a single resource file use the same encoding.
             * For example,
             * localized software may have some (but not all) of its resource names translated.
             * For non-Western languages,
             * this can lead to some resource names using MacRoman,
             * and others using a different encoding.
             */
            public byte[] value() { return value; }
            public ResourceFork _root() { return _root; }
            public ResourceFork.ResourceMap.TypeListAndReferenceLists.ReferenceList.Reference _parent() { return _parent; }
        }
        private TypeListAndReferenceLists typeListAndReferenceLists;

        /**
         * The resource map's resource type list, followed by the resource reference list area.
         */
        public TypeListAndReferenceLists typeListAndReferenceLists() {
            if (this.typeListAndReferenceLists != null)
                return this.typeListAndReferenceLists;
            long _pos = this._io.pos();
            this._io.seek(ofsTypeList());
            this._raw_typeListAndReferenceLists = this._io.readBytes((ofsNames() - ofsTypeList()));
            KaitaiStream _io__raw_typeListAndReferenceLists = new ByteBufferKaitaiStream(_raw_typeListAndReferenceLists);
            this.typeListAndReferenceLists = new TypeListAndReferenceLists(_io__raw_typeListAndReferenceLists, this, _root);
            this._io.seek(_pos);
            return this.typeListAndReferenceLists;
        }
        private BytesWithIo namesWithIo;

        /**
         * Use `names` instead,
         * unless you need access to this instance's `_io`.
         */
        public BytesWithIo namesWithIo() {
            if (this.namesWithIo != null)
                return this.namesWithIo;
            long _pos = this._io.pos();
            this._io.seek(ofsNames());
            this._raw_namesWithIo = this._io.readBytesFull();
            KaitaiStream _io__raw_namesWithIo = new ByteBufferKaitaiStream(_raw_namesWithIo);
            this.namesWithIo = new BytesWithIo(_io__raw_namesWithIo);
            this._io.seek(_pos);
            return this.namesWithIo;
        }
        private byte[] names;

        /**
         * Storage area for the names of all resources.
         */
        public byte[] names() {
            if (this.names != null)
                return this.names;
            this.names = namesWithIo().data();
            return this.names;
        }
        private FileHeader reservedFileHeaderCopy;
        private long reservedNextResourceMapHandle;
        private int reservedFileReferenceNumber;
        private FileAttributes fileAttributes;
        private int ofsTypeList;
        private int ofsNames;
        private ResourceFork _root;
        private ResourceFork _parent;
        private byte[] _raw_fileAttributes;
        private byte[] _raw_typeListAndReferenceLists;
        private byte[] _raw_namesWithIo;

        /**
         * Reserved space for a copy of the resource file header.
         */
        public FileHeader reservedFileHeaderCopy() { return reservedFileHeaderCopy; }

        /**
         * Reserved space for a handle to the next loaded resource map in memory.
         */
        public long reservedNextResourceMapHandle() { return reservedNextResourceMapHandle; }

        /**
         * Reserved space for the resource file's file reference number.
         */
        public int reservedFileReferenceNumber() { return reservedFileReferenceNumber; }

        /**
         * The resource file's attributes.
         */
        public FileAttributes fileAttributes() { return fileAttributes; }

        /**
         * Offset of the resource type list,
         * from the start of the resource map.
         * 
         * In practice,
         * this should always be `sizeof<resource_map>`,
         * i. e. the resource type list should directly follow the resource map.
         */
        public int ofsTypeList() { return ofsTypeList; }

        /**
         * Offset of the resource name area,
         * from the start of the resource map.
         */
        public int ofsNames() { return ofsNames; }
        public ResourceFork _root() { return _root; }
        public ResourceFork _parent() { return _parent; }
        public byte[] _raw_fileAttributes() { return _raw_fileAttributes; }
        public byte[] _raw_typeListAndReferenceLists() { return _raw_typeListAndReferenceLists; }
        public byte[] _raw_namesWithIo() { return _raw_namesWithIo; }
    }
    private BytesWithIo dataBlocksWithIo;

    /**
     * Use `data_blocks` instead,
     * unless you need access to this instance's `_io`.
     */
    public BytesWithIo dataBlocksWithIo() {
        if (this.dataBlocksWithIo != null)
            return this.dataBlocksWithIo;
        long _pos = this._io.pos();
        this._io.seek(header().ofsDataBlocks());
        this._raw_dataBlocksWithIo = this._io.readBytes(header().lenDataBlocks());
        KaitaiStream _io__raw_dataBlocksWithIo = new ByteBufferKaitaiStream(_raw_dataBlocksWithIo);
        this.dataBlocksWithIo = new BytesWithIo(_io__raw_dataBlocksWithIo);
        this._io.seek(_pos);
        return this.dataBlocksWithIo;
    }
    private byte[] dataBlocks;

    /**
     * Storage area for the data blocks of all resources.
     * 
     * These data blocks are not required to appear in any particular order,
     * and there may be unused space between and around them.
     * 
     * In practice,
     * the data blocks in newly created resource files are usually contiguous.
     * When existing resources are shortened,
     * the Mac OS resource manager leaves unused space where the now removed resource data was,
     * as this is quicker than moving the following resource data into the newly freed space.
     * Such unused space may be cleaned up later when the resource manager "compacts" the resource file,
     * which happens when resources are removed entirely,
     * or when resources are added or grown so that more space is needed in the data area.
     */
    public byte[] dataBlocks() {
        if (this.dataBlocks != null)
            return this.dataBlocks;
        this.dataBlocks = dataBlocksWithIo().data();
        return this.dataBlocks;
    }
    private ResourceMap resourceMap;

    /**
     * The resource file's resource map.
     */
    public ResourceMap resourceMap() {
        if (this.resourceMap != null)
            return this.resourceMap;
        long _pos = this._io.pos();
        this._io.seek(header().ofsResourceMap());
        this._raw_resourceMap = this._io.readBytes(header().lenResourceMap());
        KaitaiStream _io__raw_resourceMap = new ByteBufferKaitaiStream(_raw_resourceMap);
        this.resourceMap = new ResourceMap(_io__raw_resourceMap, this, _root);
        this._io.seek(_pos);
        return this.resourceMap;
    }
    private FileHeader header;
    private byte[] systemData;
    private byte[] applicationData;
    private ResourceFork _root;
    private KaitaiStruct _parent;
    private byte[] _raw_dataBlocksWithIo;
    private byte[] _raw_resourceMap;

    /**
     * The resource file's header information.
     */
    public FileHeader header() { return header; }

    /**
     * System-reserved data area.
     * This field can generally be ignored when reading and writing.
     * 
     * This field is used by the Classic Mac OS Finder as temporary storage space.
     * It usually contains parts of the file metadata (name, type/creator code, etc.).
     * Any existing data in this field is ignored and overwritten.
     * 
     * In resource files written by Mac OS X,
     * this field is set to all zero bytes.
     */
    public byte[] systemData() { return systemData; }

    /**
     * Application-specific data area.
     * This field can generally be ignored when reading and writing.
     * 
     * According to early revisions of Inside Macintosh,
     * this field is "available for application data".
     * In practice, it is almost never used for this purpose,
     * and usually contains only junk data.
     * 
     * In resource files written by Mac OS X,
     * this field is set to all zero bytes.
     */
    public byte[] applicationData() { return applicationData; }
    public ResourceFork _root() { return _root; }
    public KaitaiStruct _parent() { return _parent; }
    public byte[] _raw_dataBlocksWithIo() { return _raw_dataBlocksWithIo; }
    public byte[] _raw_resourceMap() { return _raw_resourceMap; }
}