Copyright (c) 2000, 2008 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) 2000, 2008 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.compiler.codegen;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.jdt.core.compiler.CharOperation;
import org.eclipse.jdt.internal.compiler.lookup.ArrayBinding;
import org.eclipse.jdt.internal.compiler.lookup.Scope;
import org.eclipse.jdt.internal.compiler.lookup.TypeBinding;
import org.eclipse.jdt.internal.compiler.lookup.TypeIds;

public class VerificationTypeInfo {
	
The tag value representing top variable info
Since:
3.2/**
	 * The tag value representing top variable info
	 * 
	 * @since 3.2
	 */
	public static final int ITEM_TOP = 0;
	
The tag value representing integer variable info
Since:
3.2/**
	 * The tag value representing integer variable info
	 * 
	 * @since 3.2
	 */
	public static final int ITEM_INTEGER = 1;
	
The tag value representing float variable info
Since:
3.2/**
	 * The tag value representing float variable info
	 * 
	 * @since 3.2
	 */
	public static final int ITEM_FLOAT = 2;
	
The tag value representing double variable info
Since:
3.2/**
	 * The tag value representing double variable info
	 * 
	 * @since 3.2
	 */
	public static final int ITEM_DOUBLE = 3;
	
The tag value representing long variable info
Since:
3.2/**
	 * The tag value representing long variable info
	 * 
	 * @since 3.2
	 */
	public static final int ITEM_LONG = 4;
	
The tag value representing null variable info
Since:
3.2/**
	 * The tag value representing null variable info
	 * 
	 * @since 3.2
	 */
	public static final int ITEM_NULL = 5;
	
The tag value representing uninitialized this variable info
Since:
3.2/**
	 * The tag value representing uninitialized this variable info
	 * 
	 * @since 3.2
	 */
	public static final int ITEM_UNINITIALIZED_THIS = 6;
	
The tag value representing object variable info
Since:
3.2/**
	 * The tag value representing object variable info
	 * 
	 * @since 3.2
	 */
	public static final int ITEM_OBJECT = 7;
	
The tag value representing uninitialized variable info
Since:
3.2/**
	 * The tag value representing uninitialized variable info
	 * 
	 * @since 3.2
	 */
	public static final int ITEM_UNINITIALIZED = 8;

	public int tag;
	private int id;
	private TypeBinding binding;
	public int offset; // where the new opcode is used
	private List<TypeBinding> bindings;

	public VerificationTypeInfo(int tag, TypeBinding binding) {
		this(binding);
		this.tag = tag;
	}

	public VerificationTypeInfo(TypeBinding binding) {
		if (binding == null) return;
		this.id = binding.id;
		this.binding = binding;
		switch (binding.id) {
			case TypeIds.T_boolean:
			case TypeIds.T_byte:
			case TypeIds.T_char:
			case TypeIds.T_int:
			case TypeIds.T_short:
				this.tag = VerificationTypeInfo.ITEM_INTEGER;
				break;
			case TypeIds.T_float:
				this.tag = VerificationTypeInfo.ITEM_FLOAT;
				break;
			case TypeIds.T_long:
				this.tag = VerificationTypeInfo.ITEM_LONG;
				break;
			case TypeIds.T_double:
				this.tag = VerificationTypeInfo.ITEM_DOUBLE;
				break;
			case TypeIds.T_null:
				this.tag = VerificationTypeInfo.ITEM_NULL;
				break;
			default:
				this.tag = VerificationTypeInfo.ITEM_OBJECT;
		}
	}

	public void setBinding(TypeBinding binding) {
		final int typeBindingId = binding.id;
		this.id = typeBindingId;
		switch (typeBindingId) {
			case TypeIds.T_boolean:
			case TypeIds.T_byte:
			case TypeIds.T_char:
			case TypeIds.T_int:
			case TypeIds.T_short:
				this.tag = VerificationTypeInfo.ITEM_INTEGER;
				break;
			case TypeIds.T_float:
				this.tag = VerificationTypeInfo.ITEM_FLOAT;
				break;
			case TypeIds.T_long:
				this.tag = VerificationTypeInfo.ITEM_LONG;
				break;
			case TypeIds.T_double:
				this.tag = VerificationTypeInfo.ITEM_DOUBLE;
				break;
			case TypeIds.T_null:
				this.tag = VerificationTypeInfo.ITEM_NULL;
				break;
			default:
				this.tag = VerificationTypeInfo.ITEM_OBJECT;
		}
	}

	public int id() {
		return this.id;
	}

	@Override
	public String toString() {
		StringBuffer buffer = new StringBuffer();
		switch (this.tag) {
			case VerificationTypeInfo.ITEM_UNINITIALIZED_THIS:
				buffer.append("uninitialized_this(").append(readableName()).append(")"); //$NON-NLS-1$//$NON-NLS-2$
				break;
			case VerificationTypeInfo.ITEM_UNINITIALIZED:
				buffer.append("uninitialized(").append(readableName()).append(")"); //$NON-NLS-1$//$NON-NLS-2$
				break;
			case VerificationTypeInfo.ITEM_OBJECT:
				buffer.append(readableName());
				break;
			case VerificationTypeInfo.ITEM_DOUBLE:
				buffer.append('D');
				break;
			case VerificationTypeInfo.ITEM_FLOAT:
				buffer.append('F');
				break;
			case VerificationTypeInfo.ITEM_INTEGER:
				buffer.append('I');
				break;
			case VerificationTypeInfo.ITEM_LONG:
				buffer.append('J');
				break;
			case VerificationTypeInfo.ITEM_NULL:
				buffer.append("null"); //$NON-NLS-1$
				break;
			case VerificationTypeInfo.ITEM_TOP:
				buffer.append("top"); //$NON-NLS-1$
				break;
		}
		return String.valueOf(buffer);
	}

	public VerificationTypeInfo duplicate() {
		VerificationTypeInfo verificationTypeInfo = new VerificationTypeInfo(this.tag, this.binding);
		verificationTypeInfo.offset = this.offset;
		return verificationTypeInfo;
	}

	@Override
	public boolean equals(Object obj) {
		if (obj instanceof VerificationTypeInfo) {
			VerificationTypeInfo info1 = (VerificationTypeInfo) obj;
			return info1.tag == this.tag && CharOperation.equals(info1.constantPoolName(), constantPoolName());
		}
		return false;
	}

	@Override
	public int hashCode() {
		return this.tag + this.id + this.binding.constantPoolName().length;
	}

	public char[] constantPoolName() {
		return this.binding.constantPoolName();
	}

	public char[] readableName() {
		return this.constantPoolName();
	}

	public void replaceWithElementType() {
		ArrayBinding arrayBinding = (ArrayBinding) this.binding;
		this.binding = arrayBinding.elementsType();
		this.id = this.binding.id;
	}

	public VerificationTypeInfo merge(VerificationTypeInfo verificationTypeInfo, Scope scope) {
		if (this.binding.isBaseType() && verificationTypeInfo.binding.isBaseType()) {
			return this;
		}
		if (!this.binding.equals(verificationTypeInfo.binding)) {
			if (this.bindings == null) {
				this.bindings = new ArrayList<TypeBinding>();
				this.bindings.add(this.binding);
			}
			this.bindings.add(verificationTypeInfo.binding);
			this.binding = scope.lowerUpperBound(this.bindings.toArray(new TypeBinding[this.bindings.size()]));
			if (this.binding != null) {
				this.id = this.binding.id;
				switch (this.id) {
					case TypeIds.T_null:
						this.tag = VerificationTypeInfo.ITEM_NULL;
						break;
					default:
						this.tag = VerificationTypeInfo.ITEM_OBJECT;
				}
			} else {
				this.binding = scope.getJavaLangObject();
				this.tag = VerificationTypeInfo.ITEM_OBJECT;
			}
		}
		return this;
	}
}