Copyright (c) 2017 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
/*******************************************************************************
 * Copyright (c) 2017 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
 *******************************************************************************/
package org.eclipse.jdt.internal.core.util;

import org.eclipse.jdt.core.util.ClassFormatException;
import org.eclipse.jdt.core.util.IConstantPool;
import org.eclipse.jdt.core.util.IConstantPoolConstant;
import org.eclipse.jdt.core.util.IConstantPoolEntry;
import org.eclipse.jdt.core.util.IProvidesInfo;

public class ProvidesInfo extends ClassFileStruct implements IProvidesInfo {
	private int index;
	private char[] serviceName;
	private int implementationsCount;
	private int[] implementationIndices;
	private char[][] implementationNames;

	public ProvidesInfo(byte[] classFileBytes, IConstantPool constantPool, int offset) throws ClassFormatException {
		int readOffset = 0;
		this.index = u2At(classFileBytes, readOffset, offset);
		readOffset += 2;
		IConstantPoolEntry constantPoolEntry = constantPool.decodeEntry(this.index);
		if (constantPoolEntry.getKind() != IConstantPoolConstant.CONSTANT_Class) {
			throw new ClassFormatException(ClassFormatException.INVALID_CONSTANT_POOL_ENTRY);
		}
		this.serviceName = constantPoolEntry.getClassInfoName();
		this.implementationsCount = u2At(classFileBytes, readOffset, offset);
		readOffset += 2;

		if (this.implementationsCount != 0) {
			this.implementationIndices = new int[this.implementationsCount];
			this.implementationNames = new char[this.implementationsCount][];
			for (int i = 0; i < this.implementationsCount; i++) {
				this.implementationIndices[i] = u2At(classFileBytes, readOffset, offset);
				readOffset += 2;
				constantPoolEntry = constantPool.decodeEntry(this.implementationIndices[i]);
				if (constantPoolEntry.getKind() != IConstantPoolConstant.CONSTANT_Class) {
					throw new ClassFormatException(ClassFormatException.INVALID_CONSTANT_POOL_ENTRY);
				}
				this.implementationNames[i] = constantPoolEntry.getClassInfoName();
			}
		}
	}
	@Override
	public int getIndex() {
		return this.index;
	}

	@Override
	public char[] getServiceName() {
		return this.serviceName;
	}

	@Override
	public int getImplementationsCount() {
		return this.implementationsCount;
	}

	@Override
	public int[] getImplementationIndices() {
		return this.implementationIndices;
	}

	@Override
	public char[][] getImplementationNames() {
		return this.implementationNames;
	}

}