Copyright (c) 2000, 2019 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
    Stephan Herrmann - Contribution for
							Bug 440477 - [null] Infrastructure for feeding external annotations into compilation
    Karsten Thoms - Bug 532505
    Sebastian Zarnekow - Contribution for
							Bug 545491 - Poor performance of ReferenceCollection with many source files
/*******************************************************************************
 * Copyright (c) 2000, 2019 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *     Stephan Herrmann - Contribution for
 *								Bug 440477 - [null] Infrastructure for feeding external annotations into compilation
 *     Karsten Thoms - Bug 532505
 *     Sebastian Zarnekow - Contribution for
 *								Bug 545491 - Poor performance of ReferenceCollection with many source files
 *******************************************************************************/
package org.eclipse.jdt.internal.core.builder;

import org.eclipse.core.resources.*;
import org.eclipse.core.runtime.*;
import org.eclipse.jdt.core.compiler.CharOperation;
import org.eclipse.jdt.internal.compiler.env.AccessRuleSet;
import org.eclipse.jdt.internal.compiler.env.IUpdatableModule;
import org.eclipse.jdt.internal.compiler.env.IUpdatableModule.*;
import org.eclipse.jdt.internal.compiler.env.AccessRule;
import org.eclipse.jdt.internal.compiler.util.SimpleLookupTable;
import org.eclipse.jdt.internal.compiler.util.Util;
import org.eclipse.jdt.internal.core.JavaModelManager;

import java.io.*;
import java.util.*;
import java.util.function.Consumer;
import java.util.stream.Collectors;

@SuppressWarnings({"rawtypes", "unchecked"})
public class State {
// NOTE: this state cannot contain types that are not defined in this project

String javaProjectName;
public ClasspathMultiDirectory[] sourceLocations;
public ClasspathMultiDirectory[] testSourceLocations;
ClasspathLocation[] binaryLocations;
ClasspathLocation[] testBinaryLocations;
// keyed by the project relative path of the type (i.e. "src1/p1/p2/A.java"), value is a ReferenceCollection or an AdditionalTypeCollection
SimpleLookupTable references;
// keyed by qualified type name "p1/p2/A", value is the project relative path which defines this type "src1/p1/p2/A.java"
public SimpleLookupTable typeLocators;

int buildNumber;
long lastStructuralBuildTime;
SimpleLookupTable structuralBuildTimes;

private String[] knownPackageNames; // of the form "p1/p2"

private long previousStructuralBuildTime;
private StringSet structurallyChangedTypes;
public static int MaxStructurallyChangedTypes = 100; // keep track of ? structurally changed types, otherwise consider all to be changed

public static final byte VERSION = 0x0022;

static final byte SOURCE_FOLDER = 1;
static final byte BINARY_FOLDER = 2;
static final byte EXTERNAL_JAR = 3;
static final byte INTERNAL_JAR = 4;

State() {
	// constructor with no argument
}

protected State(JavaBuilder javaBuilder) {
	this.knownPackageNames = null;
	this.previousStructuralBuildTime = -1;
	this.structurallyChangedTypes = null;
	this.javaProjectName = javaBuilder.currentProject.getName();
	this.sourceLocations = javaBuilder.nameEnvironment.sourceLocations;
	this.binaryLocations = javaBuilder.nameEnvironment.binaryLocations;
	this.testSourceLocations = javaBuilder.testNameEnvironment.sourceLocations;
	this.testBinaryLocations = javaBuilder.testNameEnvironment.binaryLocations;
	this.references = new SimpleLookupTable(7);
	this.typeLocators = new SimpleLookupTable(7);

	this.buildNumber = 0; // indicates a full build
	this.lastStructuralBuildTime = computeStructuralBuildTime(javaBuilder.lastState == null ? 0 : javaBuilder.lastState.lastStructuralBuildTime);
	this.structuralBuildTimes = new SimpleLookupTable(3);
}

long computeStructuralBuildTime(long previousTime) {
	long newTime = System.currentTimeMillis();
	if (newTime <= previousTime)
		newTime = previousTime + 1;
	return newTime;
}

void copyFrom(State lastState) {
	this.knownPackageNames = null;
	this.previousStructuralBuildTime = lastState.previousStructuralBuildTime;
	this.structurallyChangedTypes = lastState.structurallyChangedTypes;
	this.buildNumber = lastState.buildNumber + 1;
	this.lastStructuralBuildTime = lastState.lastStructuralBuildTime;
	this.structuralBuildTimes = lastState.structuralBuildTimes;

	try {
		this.references = (SimpleLookupTable) lastState.references.clone();
		this.typeLocators = (SimpleLookupTable) lastState.typeLocators.clone();
	} catch (CloneNotSupportedException e) {
		this.references = new SimpleLookupTable(lastState.references.elementSize);
		Object[] keyTable = lastState.references.keyTable;
		Object[] valueTable = lastState.references.valueTable;
		for (int i = 0, l = keyTable.length; i < l; i++)
			if (keyTable[i] != null)
				this.references.put(keyTable[i], valueTable[i]);

		this.typeLocators = new SimpleLookupTable(lastState.typeLocators.elementSize);
		keyTable = lastState.typeLocators.keyTable;
		valueTable = lastState.typeLocators.valueTable;
		for (int i = 0, l = keyTable.length; i < l; i++)
			if (keyTable[i] != null)
				this.typeLocators.put(keyTable[i], valueTable[i]);
	}
}
public char[][] getDefinedTypeNamesFor(String typeLocator) {
	Object c = this.references.get(typeLocator);
	if (c instanceof AdditionalTypeCollection)
		return ((AdditionalTypeCollection) c).definedTypeNames;
	return null; // means only one type is defined with the same name as the file... saves space
}

public SimpleLookupTable getReferences() {
	return this.references;
}

StringSet getStructurallyChangedTypes(State prereqState) {
	if (prereqState != null && prereqState.previousStructuralBuildTime > 0) {
		Object o = this.structuralBuildTimes.get(prereqState.javaProjectName);
		long previous = o == null ? 0 : ((Long) o).longValue();
		if (previous == prereqState.previousStructuralBuildTime)
			return prereqState.structurallyChangedTypes;
	}
	return null;
}

public boolean isDuplicateLocator(String qualifiedTypeName, String typeLocator) {
	String existing = (String) this.typeLocators.get(qualifiedTypeName);
	return existing != null && !existing.equals(typeLocator);
}

public boolean isKnownPackage(String qualifiedPackageName) {
	if (this.knownPackageNames == null) {
		LinkedHashSet<String> names = new LinkedHashSet<>(this.typeLocators.elementSize);
		Object[] keyTable = this.typeLocators.keyTable;
		for (int i = 0, l = keyTable.length; i < l; i++) {
			if (keyTable[i] != null) {
				String packageName = (String) keyTable[i]; // is a type name of the form p1/p2/A
				int last = packageName.lastIndexOf('/');
				packageName = last == -1 ? null : packageName.substring(0, last);
				while (packageName != null && !names.contains(packageName)) {
					names.add(packageName);
					last = packageName.lastIndexOf('/');
					packageName = last == -1 ? null : packageName.substring(0, last);
				}
			}
		}
		this.knownPackageNames = new String[names.size()];
		names.toArray(this.knownPackageNames);
	}
	for (int i = 0, l = this.knownPackageNames.length; i < l; i++)
		if (this.knownPackageNames[i].equals(qualifiedPackageName))
			return true;
	return false;
}

public boolean isKnownType(String qualifiedTypeName) {
	return this.typeLocators.containsKey(qualifiedTypeName);
}

boolean isSourceFolderEmpty(IContainer sourceFolder) {
	String sourceFolderName = sourceFolder.getProjectRelativePath().addTrailingSeparator().toString();
	Object[] table = this.typeLocators.valueTable;
	for (int i = 0, l = table.length; i < l; i++)
		if (table[i] != null && ((String) table[i]).startsWith(sourceFolderName))
			return false;
	return true;
}

void record(String typeLocator, char[][][] qualifiedRefs, char[][] simpleRefs, char[][] rootRefs, char[] mainTypeName, ArrayList typeNames) {
	if (typeNames.size() == 1 && CharOperation.equals(mainTypeName, (char[]) typeNames.get(0))) {
		this.references.put(typeLocator, new ReferenceCollection(qualifiedRefs, simpleRefs, rootRefs));
	} else {
		char[][] definedTypeNames = new char[typeNames.size()][]; // can be empty when no types are defined
		typeNames.toArray(definedTypeNames);
		this.references.put(typeLocator, new AdditionalTypeCollection(definedTypeNames, qualifiedRefs, simpleRefs, rootRefs));
	}
}

void recordLocatorForType(String qualifiedTypeName, String typeLocator) {
	this.knownPackageNames = null;
	// in the common case, the qualifiedTypeName is a substring of the typeLocator so share the char[] by using String.substring()
	int start = typeLocator.indexOf(qualifiedTypeName, 0);
	if (start > 0)
		qualifiedTypeName = typeLocator.substring(start, start + qualifiedTypeName.length());
	this.typeLocators.put(qualifiedTypeName, typeLocator);
}

void recordStructuralDependency(IProject prereqProject, State prereqState) {
	if (prereqState != null)
		if (prereqState.lastStructuralBuildTime > 0) // can skip if 0 (full build) since its assumed to be 0 if unknown
			this.structuralBuildTimes.put(prereqProject.getName(), Long.valueOf(prereqState.lastStructuralBuildTime));
}

void removeLocator(String typeLocatorToRemove) {
	this.knownPackageNames = null;
	this.references.removeKey(typeLocatorToRemove);
	this.typeLocators.removeValue(typeLocatorToRemove);
}

void removePackage(IResourceDelta sourceDelta) {
	IResource resource = sourceDelta.getResource();
	switch(resource.getType()) {
		case IResource.FOLDER :
			IResourceDelta[] children = sourceDelta.getAffectedChildren();
			for (int i = 0, l = children.length; i < l; i++)
				removePackage(children[i]);
			return;
		case IResource.FILE :
			IPath typeLocatorPath = resource.getProjectRelativePath();
			if (org.eclipse.jdt.internal.core.util.Util.isJavaLikeFileName(typeLocatorPath.lastSegment()))
				removeLocator(typeLocatorPath.toString());
	}
}

void removeQualifiedTypeName(String qualifiedTypeNameToRemove) {
	this.knownPackageNames = null;
	this.typeLocators.removeKey(qualifiedTypeNameToRemove);
}

static State read(IProject project, DataInputStream in) throws IOException, CoreException {
	if (JavaBuilder.DEBUG)
		System.out.println("About to read state " + project.getName()); //$NON-NLS-1$
	if (VERSION != in.readByte()) {
		if (JavaBuilder.DEBUG)
			System.out.println("Found non-compatible state version... answered null for " + project.getName()); //$NON-NLS-1$
		return null;
	}

	State newState = new State();
	newState.javaProjectName = in.readUTF();
	if (!project.getName().equals(newState.javaProjectName)) {
		if (JavaBuilder.DEBUG)
			System.out.println("Project's name does not match... answered null"); //$NON-NLS-1$
		return null;
	}
	newState.buildNumber = in.readInt();
	newState.lastStructuralBuildTime = in.readLong();

	int length = in.readInt();
	newState.sourceLocations = new ClasspathMultiDirectory[length];
	for (int i = 0; i < length; i++) {
		IContainer sourceFolder = project, outputFolder = project;
		String folderName;
		if ((folderName = in.readUTF()).length() > 0) sourceFolder = project.getFolder(folderName);
		if ((folderName = in.readUTF()).length() > 0) outputFolder = project.getFolder(folderName);
		ClasspathMultiDirectory md =
			(ClasspathMultiDirectory) ClasspathLocation.forSourceFolder(sourceFolder, outputFolder, readNames(in), readNames(in), in.readBoolean());
		if (in.readBoolean())
			md.hasIndependentOutputFolder = true;
		newState.sourceLocations[i] = md;
	}

	length = in.readInt();
	newState.binaryLocations = new ClasspathLocation[length];
	IWorkspaceRoot root = project.getWorkspace().getRoot();
	for (int i = 0; i < length; i++) {
		switch (in.readByte()) {
			case SOURCE_FOLDER :
				newState.binaryLocations[i] = newState.sourceLocations[in.readInt()];
				break;
			case BINARY_FOLDER :
				IPath path = new Path(in.readUTF());
				IContainer outputFolder = path.segmentCount() == 1
					? (IContainer) root.getProject(path.toString())
					: (IContainer) root.getFolder(path);
					newState.binaryLocations[i] = ClasspathLocation.forBinaryFolder(outputFolder, in.readBoolean(),
							readRestriction(in), new Path(in.readUTF()), in.readBoolean());
				break;
			case EXTERNAL_JAR :
				String jarPath = in.readUTF();
				if (Util.isJrt(jarPath)) {
					newState.binaryLocations[i] = ClasspathLocation.forJrtSystem(jarPath, readRestriction(in), new Path(in.readUTF()), in.readUTF());
				} else {
					newState.binaryLocations[i] = ClasspathLocation.forLibrary(jarPath, in.readLong(),
							readRestriction(in), new Path(in.readUTF()), in.readBoolean(), in.readUTF());
				}
				break;
			case INTERNAL_JAR :
					newState.binaryLocations[i] = ClasspathLocation.forLibrary(root.getFile(new Path(in.readUTF())),
							readRestriction(in), new Path(in.readUTF()), in.readBoolean(), in.readUTF());
					break;
		}
		ClasspathLocation loc = newState.binaryLocations[i];
		char[] patchName = readName(in);
		loc.patchModuleName = patchName.length > 0 ? new String(patchName) : null;
		int limitSize = in.readInt();
		if (limitSize != 0) {
			loc.limitModuleNames = new LinkedHashSet<>(limitSize);
			for (int j = 0; j < limitSize; j++) {
				loc.limitModuleNames.add(in.readUTF());
			}
		} else {
			loc.limitModuleNames = null;
		}
		IUpdatableModule.UpdatesByKind updates = new IUpdatableModule.UpdatesByKind();
		List<Consumer<IUpdatableModule>> packageUpdates = null;
		int packageUpdatesSize = in.readInt();
		if (packageUpdatesSize != 0) {
			packageUpdates = updates.getList(UpdateKind.PACKAGE, true);
			for (int j = 0; j < packageUpdatesSize; j++) {
				char[] pkgName = readName(in);
				char[][] targets = readNames(in);
				packageUpdates.add(new AddExports(pkgName, targets));
			}
		}
		List<Consumer<IUpdatableModule>> moduleUpdates = null;
		int moduleUpdatesSize = in.readInt();
		if (moduleUpdatesSize != 0) {
			moduleUpdates = updates.getList(UpdateKind.MODULE, true);
			char[] modName = readName(in);
			moduleUpdates.add(new AddReads(modName));
		}
		if (packageUpdates != null || moduleUpdates != null)
			loc.updates = updates;
	}

	length = in.readInt();
	newState.testSourceLocations = new ClasspathMultiDirectory[length];
	for (int i = 0; i < length; i++) {
		IContainer sourceFolder = project, outputFolder = project;
		String folderName;
		if ((folderName = in.readUTF()).length() > 0) sourceFolder = project.getFolder(folderName);
		if ((folderName = in.readUTF()).length() > 0) outputFolder = project.getFolder(folderName);
		ClasspathMultiDirectory md =
			(ClasspathMultiDirectory) ClasspathLocation.forSourceFolder(sourceFolder, outputFolder, readNames(in), readNames(in), in.readBoolean());
		if (in.readBoolean())
			md.hasIndependentOutputFolder = true;
		newState.testSourceLocations[i] = md;
	}

	length = in.readInt();
	newState.testBinaryLocations = new ClasspathLocation[length];
	for (int i = 0; i < length; i++) {
		switch (in.readByte()) {
			case SOURCE_FOLDER :
				newState.testBinaryLocations[i] = newState.testSourceLocations[in.readInt()];
				break;
			case BINARY_FOLDER :
				IPath path = new Path(in.readUTF());
				IContainer outputFolder = path.segmentCount() == 1
					? (IContainer) root.getProject(path.toString())
					: (IContainer) root.getFolder(path);
					newState.testBinaryLocations[i] = ClasspathLocation.forBinaryFolder(outputFolder, in.readBoolean(),
							readRestriction(in), new Path(in.readUTF()), in.readBoolean());
				break;
			case EXTERNAL_JAR :
				String jarPath = in.readUTF();
				if (Util.isJrt(jarPath)) {
					newState.testBinaryLocations[i] = ClasspathLocation.forJrtSystem(jarPath, readRestriction(in), new Path(in.readUTF()), in.readUTF());
				} else {
						newState.testBinaryLocations[i] = ClasspathLocation.forLibrary(jarPath, in.readLong(),
								readRestriction(in), new Path(in.readUTF()), in.readBoolean(), in.readUTF());
				}
				break;
			case INTERNAL_JAR :
					newState.testBinaryLocations[i] = ClasspathLocation.forLibrary(root.getFile(new Path(in.readUTF())),
							readRestriction(in), new Path(in.readUTF()), in.readBoolean(), in.readUTF());
					break;
		}
	}

	newState.structuralBuildTimes = new SimpleLookupTable(length = in.readInt());
	for (int i = 0; i < length; i++)
		newState.structuralBuildTimes.put(in.readUTF(), Long.valueOf(in.readLong()));

	String[] internedTypeLocators = new String[length = in.readInt()];
	for (int i = 0; i < length; i++)
		internedTypeLocators[i] = in.readUTF();

	newState.typeLocators = new SimpleLookupTable(length = in.readInt());
	for (int i = 0; i < length; i++)
		newState.recordLocatorForType(in.readUTF(), internedTypeLocators[in.readInt()]);

	/*
	 * Here we read global arrays of names for the entire project - do not mess up the ordering while interning
	 */
	char[][] internedRootNames = ReferenceCollection.internSimpleNames(readNames(in), false /* keep well known */, false /* do not sort */);
	char[][] internedSimpleNames = ReferenceCollection.internSimpleNames(readNames(in), false /* keep well known */, false /* do not sort */);
	char[][][] internedQualifiedNames = new char[length = in.readInt()][][];
	for (int i = 0; i < length; i++) {
		int qLength = in.readInt();
		char[][] qName = new char[qLength][];
		for (int j = 0; j < qLength; j++)
			qName[j] = internedSimpleNames[in.readInt()];
		internedQualifiedNames[i] = qName;
	}
	internedQualifiedNames = ReferenceCollection.internQualifiedNames(internedQualifiedNames, false /* drop well known */, false /* do not sort */);

	newState.references = new SimpleLookupTable(length = in.readInt());
	for (int i = 0; i < length; i++) {
		String typeLocator = internedTypeLocators[in.readInt()];
		ReferenceCollection collection = null;
		switch (in.readByte()) {
			case 1 :
				char[][] additionalTypeNames = readNames(in);
				char[][][] qualifiedNames = new char[in.readInt()][][];
				for (int j = 0, m = qualifiedNames.length; j < m; j++)
					qualifiedNames[j] = internedQualifiedNames[in.readInt()];
				char[][] simpleNames = new char[in.readInt()][];
				for (int j = 0, m = simpleNames.length; j < m; j++)
					simpleNames[j] = internedSimpleNames[in.readInt()];
				char[][] rootNames = new char[in.readInt()][];
				for (int j = 0, m = rootNames.length; j < m; j++)
					rootNames[j] = internedRootNames[in.readInt()];
				collection = new AdditionalTypeCollection(additionalTypeNames, qualifiedNames, simpleNames, rootNames);
				break;
			case 2 :
				char[][][] qNames = new char[in.readInt()][][];
				for (int j = 0, m = qNames.length; j < m; j++)
					qNames[j] = internedQualifiedNames[in.readInt()];
				char[][] sNames = new char[in.readInt()][];
				for (int j = 0, m = sNames.length; j < m; j++)
					sNames[j] = internedSimpleNames[in.readInt()];
				char[][] rNames = new char[in.readInt()][];
				for (int j = 0, m = rNames.length; j < m; j++)
					rNames[j] = internedRootNames[in.readInt()];
				collection = new ReferenceCollection(qNames, sNames, rNames);
		}
		newState.references.put(typeLocator, collection);
	}
	if (JavaBuilder.DEBUG)
		System.out.println("Successfully read state for " + newState.javaProjectName); //$NON-NLS-1$
	return newState;
}

private static char[] readName(DataInputStream in) throws IOException {
	int nLength = in.readInt();
	char[] name = new char[nLength];
	for (int j = 0; j < nLength; j++)
		name[j] = in.readChar();
	return name;
}

private static char[][] readNames(DataInputStream in) throws IOException {
	int length = in.readInt();
	char[][] names = new char[length][];
	for (int i = 0; i < length; i++)
		names[i] = readName(in);
	return names;
}

private static AccessRuleSet readRestriction(DataInputStream in) throws IOException {
	int length = in.readInt();
	if (length == 0) return null; // no restriction specified
	AccessRule[] accessRules = new AccessRule[length];
	JavaModelManager manager = JavaModelManager.getJavaModelManager();
	for (int i = 0; i < length; i++) {
		char[] pattern = readName(in);
		int problemId = in.readInt();
		accessRules[i] = manager.getAccessRuleForProblemId(pattern,problemId);
	}
	return new AccessRuleSet(accessRules, in.readByte(), manager.intern(in.readUTF()));
}

void tagAsNoopBuild() {
	this.buildNumber = -1; // tag the project since it has no source folders and can be skipped
}

boolean wasNoopBuild() {
	return this.buildNumber == -1;
}

void tagAsStructurallyChanged() {
	this.previousStructuralBuildTime = this.lastStructuralBuildTime;
	this.structurallyChangedTypes = new StringSet(7);
	this.lastStructuralBuildTime = computeStructuralBuildTime(this.previousStructuralBuildTime);
}

boolean wasStructurallyChanged(IProject prereqProject, State prereqState) {
	if (prereqState != null) {
		Object o = this.structuralBuildTimes.get(prereqProject.getName());
		long previous = o == null ? 0 : ((Long) o).longValue();
		if (previous == prereqState.lastStructuralBuildTime) return false;
	}
	return true;
}

void wasStructurallyChanged(String typeName) {
	if (this.structurallyChangedTypes != null) {
		if (this.structurallyChangedTypes.elementSize > MaxStructurallyChangedTypes)
			this.structurallyChangedTypes = null; // too many to keep track of
		else
			this.structurallyChangedTypes.add(typeName);
	}
}

void write(DataOutputStream out) throws IOException {
	int length;
	Object[] keyTable;
	Object[] valueTable;

/*
 * byte		VERSION
 * String		project name
 * int			build number
 * int			last structural build number
*/
	out.writeByte(VERSION);
	out.writeUTF(this.javaProjectName);
	out.writeInt(this.buildNumber);
	out.writeLong(this.lastStructuralBuildTime);

/*
 * ClasspathMultiDirectory[]
 * int			id
 * String		path(s)
*/
	out.writeInt(length = this.sourceLocations.length);
	for (int i = 0; i < length; i++) {
		ClasspathMultiDirectory md = this.sourceLocations[i];
		out.writeUTF(md.sourceFolder.getProjectRelativePath().toString());
		out.writeUTF(md.binaryFolder.getProjectRelativePath().toString());
		writeNames(md.inclusionPatterns, out);
		writeNames(md.exclusionPatterns, out);
		out.writeBoolean(md.ignoreOptionalProblems);
		out.writeBoolean(md.hasIndependentOutputFolder);
	}

/*
 * ClasspathLocation[]
 * int			id
 * String		path(s)
*/
	out.writeInt(length = this.binaryLocations.length);
	for (int i = 0; i < length; i++) {
		ClasspathLocation c = this.binaryLocations[i];
		if (c instanceof ClasspathMultiDirectory) {
			out.writeByte(SOURCE_FOLDER);
			for (int j = 0, m = this.sourceLocations.length; j < m; j++) {
				if (this.sourceLocations[j] == c) {
					out.writeInt(j);
					//continue next;
				}
			}
		} else if (c instanceof ClasspathDirectory) {
			out.writeByte(BINARY_FOLDER);
			ClasspathDirectory cd = (ClasspathDirectory) c;
			out.writeUTF(cd.binaryFolder.getFullPath().toString());
			out.writeBoolean(cd.isOutputFolder);
			writeRestriction(cd.accessRuleSet, out);
			out.writeUTF(cd.externalAnnotationPath != null ? cd.externalAnnotationPath : ""); //$NON-NLS-1$
			out.writeBoolean(cd.isOnModulePath);
		} else if (c instanceof ClasspathJar) {
			ClasspathJar jar = (ClasspathJar) c;
			if (jar.resource == null) {
				out.writeByte(EXTERNAL_JAR);
				out.writeUTF(jar.zipFilename);
				out.writeLong(jar.lastModified());
			} else {
				out.writeByte(INTERNAL_JAR);
				out.writeUTF(jar.resource.getFullPath().toString());
			}
			writeRestriction(jar.accessRuleSet, out);
			out.writeUTF(jar.externalAnnotationPath != null ? jar.externalAnnotationPath : ""); //$NON-NLS-1$
			out.writeBoolean(jar.isOnModulePath);
			out.writeUTF(jar.compliance == null ? "" : jar.compliance); //$NON-NLS-1$
			
		} else if (c instanceof ClasspathJrt) {
			ClasspathJrt jrt = (ClasspathJrt) c;
			out.writeByte(EXTERNAL_JAR);
			out.writeUTF(jrt.zipFilename);
			writeRestriction(jrt.accessRuleSet, out);
			out.writeUTF(jrt.externalAnnotationPath != null ? jrt.externalAnnotationPath : ""); //$NON-NLS-1$
			out.writeUTF(""); //$NON-NLS-1$
		} else {
			ClasspathJrtWithReleaseOption jrt = (ClasspathJrtWithReleaseOption) c;
			out.writeByte(EXTERNAL_JAR);
			out.writeUTF(jrt.zipFilename);
			writeRestriction(jrt.accessRuleSet, out);
			out.writeUTF(jrt.externalAnnotationPath != null ? jrt.externalAnnotationPath : ""); //$NON-NLS-1$
			out.writeUTF(jrt.release);
		}
		char[] patchName = c.patchModuleName == null ? CharOperation.NO_CHAR : c.patchModuleName.toCharArray();
		writeName(patchName, out);
		if (c.limitModuleNames != null) {
			out.writeInt(c.limitModuleNames.size());
			for (String name : c.limitModuleNames) {
				out.writeUTF(name);
			}
		} else {
			out.writeInt(0);
		}
		if (c.updates != null) {
			List<Consumer<IUpdatableModule>> pu = c.updates.getList(UpdateKind.PACKAGE, false);
			if (pu != null) {
				Map<String, List<Consumer<IUpdatableModule>>> map = pu.stream().
						collect(Collectors.groupingBy(
								update -> CharOperation.charToString(((IUpdatableModule.AddExports)update).getName())));
				out.writeInt(map.size());
				map.entrySet().stream().forEach(entry -> {
					String pkgName = entry.getKey();
					try {
						writeName(pkgName.toCharArray(), out);
						char[][] targetModules = entry.getValue().stream()
								.map(consumer -> ((IUpdatableModule.AddExports) consumer).getTargetModules())
								.filter(targets -> targets != null)
								.reduce((f,s) -> CharOperation.arrayConcat(f,s))
								.orElse(null);
						writeNames(targetModules, out);
					} catch (IOException e) {
						// ignore
					}
					
				});
			} else {
				out.writeInt(0);
			}
			List<Consumer<IUpdatableModule>> mu = c.updates.getList(UpdateKind.MODULE, false);
			if (mu != null) {
				out.writeInt(mu.size());
				for (Consumer<IUpdatableModule> cons : mu) {
					AddReads m = (AddReads) cons;
					writeName(m.getTarget(), out);
				}
			} else {
				out.writeInt(0);
			}
		} else {
			out.writeInt(0);
			out.writeInt(0);
		}
	}
	/*
	 * ClasspathMultiDirectory[]
	 * int			id
	 * String		path(s)
	*/
		out.writeInt(length = this.testSourceLocations.length);
		for (int i = 0; i < length; i++) {
			ClasspathMultiDirectory md = this.testSourceLocations[i];
			out.writeUTF(md.sourceFolder.getProjectRelativePath().toString());
			out.writeUTF(md.binaryFolder.getProjectRelativePath().toString());
			writeNames(md.inclusionPatterns, out);
			writeNames(md.exclusionPatterns, out);
			out.writeBoolean(md.ignoreOptionalProblems);
			out.writeBoolean(md.hasIndependentOutputFolder);
		}

	/*
	 * ClasspathLocation[]
	 * int			id
	 * String		path(s)
	*/
		out.writeInt(length = this.testBinaryLocations.length);
		next : for (int i = 0; i < length; i++) {
			ClasspathLocation c = this.testBinaryLocations[i];
			if (c instanceof ClasspathMultiDirectory) {
				out.writeByte(SOURCE_FOLDER);
				for (int j = 0, m = this.testSourceLocations.length; j < m; j++) {
					if (this.testSourceLocations[j] == c) {
						out.writeInt(j);
						continue next;
					}
				}
			} else if (c instanceof ClasspathDirectory) {
				out.writeByte(BINARY_FOLDER);
				ClasspathDirectory cd = (ClasspathDirectory) c;
				out.writeUTF(cd.binaryFolder.getFullPath().toString());
				out.writeBoolean(cd.isOutputFolder);
				writeRestriction(cd.accessRuleSet, out);
				out.writeUTF(cd.externalAnnotationPath != null ? cd.externalAnnotationPath : ""); //$NON-NLS-1$
				out.writeBoolean(cd.isOnModulePath);
			} else if (c instanceof ClasspathJar) {
				ClasspathJar jar = (ClasspathJar) c;
				if (jar.resource == null) {
					out.writeByte(EXTERNAL_JAR);
					out.writeUTF(jar.zipFilename);
					out.writeLong(jar.lastModified());
				} else {
					out.writeByte(INTERNAL_JAR);
					out.writeUTF(jar.resource.getFullPath().toString());
				}
				writeRestriction(jar.accessRuleSet, out);
				out.writeUTF(jar.externalAnnotationPath != null ? jar.externalAnnotationPath : ""); //$NON-NLS-1$
				out.writeBoolean(jar.isOnModulePath);
				out.writeUTF(jar.compliance != null ? jar.compliance : ""); //$NON-NLS-1$
			} else if (c instanceof ClasspathJrt) {
				ClasspathJrt jrt = (ClasspathJrt) c;
				out.writeByte(EXTERNAL_JAR);
				out.writeUTF(jrt.zipFilename);
				writeRestriction(jrt.accessRuleSet, out);
				out.writeUTF(jrt.externalAnnotationPath != null ? jrt.externalAnnotationPath : ""); //$NON-NLS-1$
				out.writeUTF(""); //$NON-NLS-1$
			} else {
				ClasspathJrtWithReleaseOption jrt = (ClasspathJrtWithReleaseOption) c;
				out.writeByte(EXTERNAL_JAR);
				out.writeUTF(jrt.zipFilename);
				writeRestriction(jrt.accessRuleSet, out);
				out.writeUTF(jrt.externalAnnotationPath != null ? jrt.externalAnnotationPath : ""); //$NON-NLS-1$
				out.writeUTF(jrt.release);
			}
		}

/*
 * Structural build numbers table
 * String		prereq project name
 * int			last structural build number
*/
	out.writeInt(length = this.structuralBuildTimes.elementSize);
	if (length > 0) {
		keyTable = this.structuralBuildTimes.keyTable;
		valueTable = this.structuralBuildTimes.valueTable;
		for (int i = 0, l = keyTable.length; i < l; i++) {
			if (keyTable[i] != null) {
				length--;
				out.writeUTF((String) keyTable[i]);
				out.writeLong(((Long) valueTable[i]).longValue());
			}
		}
		if (JavaBuilder.DEBUG && length != 0)
			System.out.println("structuralBuildNumbers table is inconsistent"); //$NON-NLS-1$
	}

/*
 * String[]	Interned type locators
 */
	out.writeInt(length = this.references.elementSize);
	SimpleLookupTable internedTypeLocators = new SimpleLookupTable(length);
	if (length > 0) {
		keyTable = this.references.keyTable;
		for (int i = 0, l = keyTable.length; i < l; i++) {
			if (keyTable[i] != null) {
				length--;
				String key = (String) keyTable[i];
				out.writeUTF(key);
				internedTypeLocators.put(key, Integer.valueOf(internedTypeLocators.elementSize));
			}
		}
		if (JavaBuilder.DEBUG && length != 0)
			System.out.println("references table is inconsistent"); //$NON-NLS-1$
	}

/*
 * Type locators table
 * String		type name
 * int			interned locator id
 */
	out.writeInt(length = this.typeLocators.elementSize);
	if (length > 0) {
		keyTable = this.typeLocators.keyTable;
		valueTable = this.typeLocators.valueTable;
		for (int i = 0, l = keyTable.length; i < l; i++) {
			if (keyTable[i] != null) {
				length--;
				out.writeUTF((String) keyTable[i]);
				Integer index = (Integer) internedTypeLocators.get(valueTable[i]);
				out.writeInt(index.intValue());
			}
		}
		if (JavaBuilder.DEBUG && length != 0)
			System.out.println("typeLocators table is inconsistent"); //$NON-NLS-1$
	}

/*
 * char[][]	Interned root names
 * char[][][]	Interned qualified names
 * char[][]	Interned simple names
 */
	SimpleLookupTable internedRootNames = new SimpleLookupTable(3);
	SimpleLookupTable internedQualifiedNames = new SimpleLookupTable(31);
	SimpleLookupTable internedSimpleNames = new SimpleLookupTable(31);
	valueTable = this.references.valueTable;
	for (int i = 0, l = valueTable.length; i < l; i++) {
		if (valueTable[i] != null) {
			ReferenceCollection collection = (ReferenceCollection) valueTable[i];
			char[][] rNames = collection.rootReferences;
			for (int j = 0, m = rNames.length; j < m; j++) {
				char[] rName = rNames[j];
				if (!internedRootNames.containsKey(rName)) // remember the names have been interned
					internedRootNames.put(rName, Integer.valueOf(internedRootNames.elementSize));
			}
			char[][][] qNames = collection.qualifiedNameReferences;
			for (int j = 0, m = qNames.length; j < m; j++) {
				char[][] qName = qNames[j];
				if (!internedQualifiedNames.containsKey(qName)) { // remember the names have been interned
					internedQualifiedNames.put(qName, Integer.valueOf(internedQualifiedNames.elementSize));
					for (int k = 0, n = qName.length; k < n; k++) {
						char[] sName = qName[k];
						if (!internedSimpleNames.containsKey(sName)) // remember the names have been interned
							internedSimpleNames.put(sName, Integer.valueOf(internedSimpleNames.elementSize));
					}
				}
			}
			char[][] sNames = collection.simpleNameReferences;
			for (int j = 0, m = sNames.length; j < m; j++) {
				char[] sName = sNames[j];
				if (!internedSimpleNames.containsKey(sName)) // remember the names have been interned
					internedSimpleNames.put(sName, Integer.valueOf(internedSimpleNames.elementSize));
			}
		}
	}
	char[][] internedArray = new char[internedRootNames.elementSize][];
	Object[] rootNames = internedRootNames.keyTable;
	Object[] positions = internedRootNames.valueTable;
	for (int i = positions.length; --i >= 0; ) {
		if (positions[i] != null) {
			int index = ((Integer) positions[i]).intValue();
			internedArray[index] = (char[]) rootNames[i];
		}
	}
	writeNames(internedArray, out);
	// now write the interned simple names
	internedArray = new char[internedSimpleNames.elementSize][];
	Object[] simpleNames = internedSimpleNames.keyTable;
	positions = internedSimpleNames.valueTable;
	for (int i = positions.length; --i >= 0; ) {
		if (positions[i] != null) {
			int index = ((Integer) positions[i]).intValue();
			internedArray[index] = (char[]) simpleNames[i];
		}
	}
	writeNames(internedArray, out);
	// now write the interned qualified names as arrays of interned simple names
	char[][][] internedQArray = new char[internedQualifiedNames.elementSize][][];
	Object[] qualifiedNames = internedQualifiedNames.keyTable;
	positions = internedQualifiedNames.valueTable;
	for (int i = positions.length; --i >= 0; ) {
		if (positions[i] != null) {
			int index = ((Integer) positions[i]).intValue();
			internedQArray[index] = (char[][]) qualifiedNames[i];
		}
	}
	out.writeInt(length = internedQArray.length);
	for (int i = 0; i < length; i++) {
		char[][] qName = internedQArray[i];
		int qLength = qName.length;
		out.writeInt(qLength);
		for (int j = 0; j < qLength; j++) {
			Integer index = (Integer) internedSimpleNames.get(qName[j]);
			out.writeInt(index.intValue());
		}
	}

/*
 * References table
 * int		interned locator id
 * ReferenceCollection
*/
	out.writeInt(length = this.references.elementSize);
	if (length > 0) {
		keyTable = this.references.keyTable;
		for (int i = 0, l = keyTable.length; i < l; i++) {
			if (keyTable[i] != null) {
				length--;
				Integer index = (Integer) internedTypeLocators.get(keyTable[i]);
				out.writeInt(index.intValue());
				ReferenceCollection collection = (ReferenceCollection) valueTable[i];
				if (collection instanceof AdditionalTypeCollection) {
					out.writeByte(1);
					AdditionalTypeCollection atc = (AdditionalTypeCollection) collection;
					writeNames(atc.definedTypeNames, out);
				} else {
					out.writeByte(2);
				}
				char[][][] qNames = collection.qualifiedNameReferences;
				int qLength = qNames.length;
				out.writeInt(qLength);
				for (int j = 0; j < qLength; j++) {
					index = (Integer) internedQualifiedNames.get(qNames[j]);
					out.writeInt(index.intValue());
				}
				char[][] sNames = collection.simpleNameReferences;
				int sLength = sNames.length;
				out.writeInt(sLength);
				for (int j = 0; j < sLength; j++) {
					index = (Integer) internedSimpleNames.get(sNames[j]);
					out.writeInt(index.intValue());
				}
				char[][] rNames = collection.rootReferences;
				int rLength = rNames.length;
				out.writeInt(rLength);
				for (int j = 0; j < rLength; j++) {
					index = (Integer) internedRootNames.get(rNames[j]);
					out.writeInt(index.intValue());
				}
			}
		}
		if (JavaBuilder.DEBUG && length != 0)
			System.out.println("references table is inconsistent"); //$NON-NLS-1$
	}
}

private void writeName(char[] name, DataOutputStream out) throws IOException {
	int nLength = name.length;
	out.writeInt(nLength);
	for (int j = 0; j < nLength; j++)
		out.writeChar(name[j]);
}

private void writeNames(char[][] names, DataOutputStream out) throws IOException {
	int length = names == null ? 0 : names.length;
	out.writeInt(length);
	for (int i = 0; i < length; i++)
		writeName(names[i], out);
}

private void writeRestriction(AccessRuleSet accessRuleSet, DataOutputStream out) throws IOException {
	if (accessRuleSet == null) {
		out.writeInt(0);
	} else {
		AccessRule[] accessRules = accessRuleSet.getAccessRules();
		int length = accessRules.length;
		out.writeInt(length);
		if (length != 0) {
			for (int i = 0; i < length; i++) {
				AccessRule accessRule = accessRules[i];
				writeName(accessRule.pattern, out);
				out.writeInt(accessRule.problemId);
			}
			out.writeByte(accessRuleSet.classpathEntryType);
			out.writeUTF(accessRuleSet.classpathEntryName);
		}
	}
}

Returns a string representation of the receiver.
/**
 * Returns a string representation of the receiver.
 */
@Override
public String toString() {
	return "State for " + this.javaProjectName //$NON-NLS-1$
		+ " (#" + this.buildNumber //$NON-NLS-1$
			+ " @ " + new Date(this.lastStructuralBuildTime) //$NON-NLS-1$
				+ ")"; //$NON-NLS-1$
}

/* Debug helper
void dump() {
	System.out.println("State for " + javaProjectName + " (" + buildNumber + " @ " + new Date(lastStructuralBuildTime) + ")");
	System.out.println("\tClass path source locations:");
	for (int i = 0, l = sourceLocations.length; i < l; i++)
		System.out.println("\t\t" + sourceLocations[i]);
	System.out.println("\tClass path binary locations:");
	for (int i = 0, l = binaryLocations.length; i < l; i++)
		System.out.println("\t\t" + binaryLocations[i]);

	System.out.print("\tStructural build numbers table:");
	if (structuralBuildTimes.elementSize == 0) {
		System.out.print(" <empty>");
	} else {
		Object[] keyTable = structuralBuildTimes.keyTable;
		Object[] valueTable = structuralBuildTimes.valueTable;
		for (int i = 0, l = keyTable.length; i < l; i++)
			if (keyTable[i] != null)
				System.out.print("\n\t\t" + keyTable[i].toString() + " -> " + valueTable[i].toString());
	}

	System.out.print("\tType locators table:");
	if (typeLocators.elementSize == 0) {
		System.out.print(" <empty>");
	} else {
		Object[] keyTable = typeLocators.keyTable;
		Object[] valueTable = typeLocators.valueTable;
		for (int i = 0, l = keyTable.length; i < l; i++)
			if (keyTable[i] != null)
				System.out.print("\n\t\t" + keyTable[i].toString() + " -> " + valueTable[i].toString());
	}

	System.out.print("\n\tReferences table:");
	if (references.elementSize == 0) {
		System.out.print(" <empty>");
	} else {
		Object[] keyTable = references.keyTable;
		Object[] valueTable = references.valueTable;
		for (int i = 0, l = keyTable.length; i < l; i++) {
			if (keyTable[i] != null) {
				System.out.print("\n\t\t" + keyTable[i].toString());
				ReferenceCollection c = (ReferenceCollection) valueTable[i];
				char[][][] qRefs = c.qualifiedNameReferences;
				System.out.print("\n\t\t\tqualified:");
				if (qRefs.length == 0)
					System.out.print(" <empty>");
				else for (int j = 0, m = qRefs.length; j < m; j++)
						System.out.print("  '" + CharOperation.toString(qRefs[j]) + "'");
				char[][] sRefs = c.simpleNameReferences;
				System.out.print("\n\t\t\tsimple:");
				if (sRefs.length == 0)
					System.out.print(" <empty>");
				else for (int j = 0, m = sRefs.length; j < m; j++)
						System.out.print("  " + new String(sRefs[j]));
				if (c instanceof AdditionalTypeCollection) {
					char[][] names = ((AdditionalTypeCollection) c).definedTypeNames;
					System.out.print("\n\t\t\tadditional type names:");
					for (int j = 0, m = names.length; j < m; j++)
						System.out.print("  " + new String(names[j]));
				}
			}
		}
	}
	System.out.print("\n\n");
}
*/
}