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AspectJ tools most notably contains the AspectJ compiler (AJC). AJC applies aspects to Java classes during compilation, fully replacing Javac for plain Java classes and also compiling native AspectJ or annotation-based @AspectJ syntax. Furthermore, AJC can weave aspects into existing class files in a post-compile binary weaving step. This library is a superset of AspectJ weaver and hence also of AspectJ runtime.
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package org.aspectj.apache.bcel.generic;

/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2001 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (https://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Apache" and "Apache Software Foundation" and
 *    "Apache BCEL" must not be used to endorse or promote products
 *    derived from this software without prior written permission. For
 *    written permission, please contact [email protected].
 *
 * 5. Products derived from this software may not be called "Apache",
 *    "Apache BCEL", nor may "Apache" appear in their name, without
 *    prior written permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * .
 */
import org.aspectj.apache.bcel.Constants;
import org.aspectj.apache.bcel.classfile.ConstantPool;
import org.aspectj.apache.bcel.classfile.Utility;

/**
 * Instances of this class may be used, e.g., to generate typed versions of instructions. Its main purpose is to be used as the byte
 * code generating backend of a compiler. You can subclass it to add your own create methods.
 *
 * @version $Id: InstructionFactory.java,v 1.7 2010/08/23 20:44:10 aclement Exp $
 * @author M. Dahm
 * @see Constants
 */
public class InstructionFactory implements InstructionConstants {
	protected ClassGen cg;
	protected ConstantPool cp;

	public InstructionFactory(ClassGen cg, ConstantPool cp) {
		this.cg = cg;
		this.cp = cp;
	}

	public InstructionFactory(ClassGen cg) {
		this(cg, cg.getConstantPool());
	}

	public InstructionFactory(ConstantPool cp) {
		this(null, cp);
	}

	public InvokeInstruction createInvoke(String class_name, String name, Type ret_type, Type[] arg_types, short kind) {
		return createInvoke(class_name, name, ret_type, arg_types, kind, false);
	}

	/**
	 * Create an invoke instruction.
	 *
	 * @param class_name name of the called class
	 * @param name name of the called method
	 * @param ret_type return type of method
	 * @param arg_types argument types of method
	 * @param kind how to invoke, i.e., INVOKEINTERFACE, INVOKESTATIC, INVOKEVIRTUAL, or INVOKESPECIAL
	 * @param isInterface for an invokestatic on an interface allows us to tell this method the target is an interface
	 * @see Constants
	 */
	public InvokeInstruction createInvoke(String class_name, String name, Type ret_type, Type[] arg_types, short kind, boolean isInterface) {

		String signature = Utility.toMethodSignature(ret_type, arg_types);

		int index;
		if (kind == Constants.INVOKEINTERFACE || isInterface) {
			index = cp.addInterfaceMethodref(class_name, name, signature);
		} else if (kind == Constants.INVOKEDYNAMIC){
			throw new IllegalStateException("NYI");
		} else {
			index = cp.addMethodref(class_name, name, signature);
		}

		switch (kind) {
		case Constants.INVOKESPECIAL:
			return new InvokeInstruction(Constants.INVOKESPECIAL, index);
		case Constants.INVOKEVIRTUAL:
			return new InvokeInstruction(Constants.INVOKEVIRTUAL, index);
		case Constants.INVOKESTATIC:
			return new InvokeInstruction(Constants.INVOKESTATIC, index);
		case Constants.INVOKEINTERFACE:
			int nargs = 0;
			for (Type arg_type : arg_types) {
				nargs += arg_type.getSize();
			}
			return new INVOKEINTERFACE(index, nargs + 1, 0);
		default:
			throw new RuntimeException("Oops: Unknown invoke kind:" + kind);
		}
	}

	public InvokeInstruction createInvoke(String class_name, String name, String signature, short kind) {
		int index;
		if (kind == Constants.INVOKEINTERFACE) {
			index = cp.addInterfaceMethodref(class_name, name, signature);
		} else if (kind == Constants.INVOKEDYNAMIC){
			throw new IllegalStateException("NYI");
		} else {
			index = cp.addMethodref(class_name, name, signature);
		}

		switch (kind) {
		case Constants.INVOKESPECIAL:
			return new InvokeInstruction(Constants.INVOKESPECIAL, index);
		case Constants.INVOKEVIRTUAL:
			return new InvokeInstruction(Constants.INVOKEVIRTUAL, index);
		case Constants.INVOKESTATIC:
			return new InvokeInstruction(Constants.INVOKESTATIC, index);
		case Constants.INVOKEINTERFACE:
			Type[] argumentTypes = Type.getArgumentTypes(signature);
			int nargs = 0;
			for (Type argumentType : argumentTypes) {// Count size of arguments
				nargs += argumentType.getSize();
			}
			return new INVOKEINTERFACE(index, nargs + 1, 0);
		default:
			throw new RuntimeException("Oops: Unknown invoke kind:" + kind);
		}
	}

	public static Instruction createALOAD(int n) {
		if (n < 4) {
			return new InstructionLV((short) (Constants.ALOAD_0 + n));
		}
		return new InstructionLV(Constants.ALOAD, n);
	}

	public static Instruction createASTORE(int n) {
		if (n < 4) {
			return new InstructionLV((short) (Constants.ASTORE_0 + n));
		}
		return new InstructionLV(Constants.ASTORE, n);
	}

	/**
	 * Uses PUSH to push a constant value onto the stack.
	 *
	 * @param value must be of type Number, Boolean, Character or String
	 */
	// OPTIMIZE callers should use the PUSH methods where possible if they know the types
	public Instruction createConstant(Object value) {
		Instruction instruction;

		if (value instanceof Number) {
			instruction = InstructionFactory.PUSH(cp, (Number) value);
		} else if (value instanceof String) {
			instruction = InstructionFactory.PUSH(cp, (String) value);
		} else if (value instanceof Boolean) {
			instruction = InstructionFactory.PUSH(cp, (Boolean) value);
		} else if (value instanceof Character) {
			instruction = InstructionFactory.PUSH(cp, (Character) value);
		} else if (value instanceof ObjectType) {
			instruction = InstructionFactory.PUSH(cp, (ObjectType) value);
		} else {
			throw new ClassGenException("Illegal type: " + value.getClass());
		}

		return instruction;
	}

	/**
	 * Create a field instruction.
	 *
	 * @param class_name name of the accessed class
	 * @param name name of the referenced field
	 * @param type type of field
	 * @param kind how to access, i.e., GETFIELD, PUTFIELD, GETSTATIC, PUTSTATIC
	 * @see Constants
	 */
	public FieldInstruction createFieldAccess(String class_name, String name, Type type, short kind) {
		int index;
		String signature = type.getSignature();

		index = cp.addFieldref(class_name, name, signature);

		switch (kind) {
		case Constants.GETFIELD:
			return new FieldInstruction(Constants.GETFIELD, index);
		case Constants.PUTFIELD:
			return new FieldInstruction(Constants.PUTFIELD, index);
		case Constants.GETSTATIC:
			return new FieldInstruction(Constants.GETSTATIC, index);
		case Constants.PUTSTATIC:
			return new FieldInstruction(Constants.PUTSTATIC, index);

		default:
			throw new RuntimeException("Oops: Unknown getfield kind:" + kind);
		}
	}

	/**
	 * Create reference to `this'
	 */
	public static Instruction createThis() {
		return new InstructionLV(Constants.ALOAD, 0);
	}

	/**
	 * Create typed return
	 */
	public static Instruction createReturn(Type type) {
		switch (type.getType()) {
		case Constants.T_ARRAY:
		case Constants.T_OBJECT:
			return ARETURN;
		case Constants.T_INT:
		case Constants.T_SHORT:
		case Constants.T_BOOLEAN:
		case Constants.T_CHAR:
		case Constants.T_BYTE:
			return IRETURN;
		case Constants.T_FLOAT:
			return FRETURN;
		case Constants.T_DOUBLE:
			return DRETURN;
		case Constants.T_LONG:
			return LRETURN;
		case Constants.T_VOID:
			return RETURN;

		default:
			throw new RuntimeException("Invalid type: " + type);
		}
	}

	/**
	 * @param size size of operand, either 1 (int, e.g.) or 2 (double)
	 */
	public static Instruction createPop(int size) {
		return (size == 2) ? POP2 : POP;
	}

	/**
	 * @param size size of operand, either 1 (int, e.g.) or 2 (double)
	 */
	public static Instruction createDup(int size) {
		return (size == 2) ? DUP2 : DUP;
	}

	/**
	 * @param size size of operand, either 1 (int, e.g.) or 2 (double)
	 */
	public static Instruction createDup_2(int size) {
		return (size == 2) ? DUP2_X2 : DUP_X2;
	}

	/**
	 * @param size size of operand, either 1 (int, e.g.) or 2 (double)
	 */
	public static Instruction createDup_1(int size) {
		return (size == 2) ? DUP2_X1 : DUP_X1;
	}

	/**
	 * @param index index of local variable
	 */
	public static InstructionLV createStore(Type type, int index) {
		switch (type.getType()) {
		case Constants.T_BOOLEAN:
		case Constants.T_CHAR:
		case Constants.T_BYTE:
		case Constants.T_SHORT:
		case Constants.T_INT:
			return new InstructionLV(Constants.ISTORE, index);
		case Constants.T_FLOAT:
			return new InstructionLV(Constants.FSTORE, index);
		case Constants.T_DOUBLE:
			return new InstructionLV(Constants.DSTORE, index);
		case Constants.T_LONG:
			return new InstructionLV(Constants.LSTORE, index);
		case Constants.T_ARRAY:
		case Constants.T_OBJECT:
			return new InstructionLV(Constants.ASTORE, index);
		default:
			throw new RuntimeException("Invalid type " + type);
		}
	}

	/**
	 * @param index index of local variable
	 */
	public static InstructionLV createLoad(Type type, int index) {
		switch (type.getType()) {
		case Constants.T_BOOLEAN:
		case Constants.T_CHAR:
		case Constants.T_BYTE:
		case Constants.T_SHORT:
		case Constants.T_INT:
			return new InstructionLV(Constants.ILOAD, index);
		case Constants.T_FLOAT:
			return new InstructionLV(Constants.FLOAD, index);
		case Constants.T_DOUBLE:
			return new InstructionLV(Constants.DLOAD, index);
		case Constants.T_LONG:
			return new InstructionLV(Constants.LLOAD, index);
		case Constants.T_ARRAY:
		case Constants.T_OBJECT:
			return new InstructionLV(Constants.ALOAD, index);
		default:
			throw new RuntimeException("Invalid type " + type);
		}
	}

	/**
	 * @param type type of elements of array, i.e., array.getElementType()
	 */
	public static Instruction createArrayLoad(Type type) {
		switch (type.getType()) {
		case Constants.T_BOOLEAN:
		case Constants.T_BYTE:
			return BALOAD;
		case Constants.T_CHAR:
			return CALOAD;
		case Constants.T_SHORT:
			return SALOAD;
		case Constants.T_INT:
			return IALOAD;
		case Constants.T_FLOAT:
			return FALOAD;
		case Constants.T_DOUBLE:
			return DALOAD;
		case Constants.T_LONG:
			return LALOAD;
		case Constants.T_ARRAY:
		case Constants.T_OBJECT:
			return AALOAD;
		default:
			throw new RuntimeException("Invalid type " + type);
		}
	}

	/**
	 * @param type type of elements of array, i.e., array.getElementType()
	 */
	public static Instruction createArrayStore(Type type) {
		switch (type.getType()) {
		case Constants.T_BOOLEAN:
		case Constants.T_BYTE:
			return BASTORE;
		case Constants.T_CHAR:
			return CASTORE;
		case Constants.T_SHORT:
			return SASTORE;
		case Constants.T_INT:
			return IASTORE;
		case Constants.T_FLOAT:
			return FASTORE;
		case Constants.T_DOUBLE:
			return DASTORE;
		case Constants.T_LONG:
			return LASTORE;
		case Constants.T_ARRAY:
		case Constants.T_OBJECT:
			return AASTORE;
		default:
			throw new RuntimeException("Invalid type " + type);
		}
	}

	private static final char[] shortNames = { 'C', 'F', 'D', 'B', 'S', 'I', 'L' };

	/**
	 * Create conversion operation for two stack operands, this may be an I2C, instruction, e.g., if the operands are basic types
	 * and CHECKCAST if they are reference types.
	 */
	public Instruction createCast(Type src_type, Type dest_type) {
		if ((src_type instanceof BasicType) && (dest_type instanceof BasicType)) {
			byte dest = dest_type.getType();
			byte src = src_type.getType();

			if (dest == Constants.T_LONG && (src == Constants.T_CHAR || src == Constants.T_BYTE || src == Constants.T_SHORT)) {
				src = Constants.T_INT;
			}

			if (src == Constants.T_DOUBLE) {
				switch (dest) {
				case Constants.T_FLOAT:
					return InstructionConstants.D2F;
				case Constants.T_INT:
					return InstructionConstants.D2I;
				case Constants.T_LONG:
					return InstructionConstants.D2L;
				}
			} else if (src == Constants.T_FLOAT) {
				switch (dest) {
				case Constants.T_DOUBLE:
					return InstructionConstants.F2D;
				case Constants.T_INT:
					return InstructionConstants.F2I;
				case Constants.T_LONG:
					return InstructionConstants.F2L;
				}
			} else if (src == Constants.T_INT) {
				switch (dest) {
				case Constants.T_BYTE:
					return InstructionConstants.I2B;
				case Constants.T_CHAR:
					return InstructionConstants.I2C;
				case Constants.T_DOUBLE:
					return InstructionConstants.I2D;
				case Constants.T_FLOAT:
					return InstructionConstants.I2F;
				case Constants.T_LONG:
					return InstructionConstants.I2L;
				case Constants.T_SHORT:
					return InstructionConstants.I2S;
				}
			} else if (src == Constants.T_LONG) {
				switch (dest) {
				case Constants.T_DOUBLE:
					return InstructionConstants.L2D;
				case Constants.T_FLOAT:
					return InstructionConstants.L2F;
				case Constants.T_INT:
					return InstructionConstants.L2I;
				}
			}

			// String name = "org.aspectj.apache.bcel.generic." + short_names[src - Constants.T_CHAR] +
			// "2" + short_names[dest - Constants.T_CHAR];

			// Instruction i = null;
			// try {
			// i = (Instruction)java.lang.Class.forName(name).newInstance();
			// } catch(Exception e) {
			// throw new RuntimeException("Could not find instruction: " + name);
			// }

			return null;
			// return i;
		} else if ((src_type instanceof ReferenceType) && (dest_type instanceof ReferenceType)) {
			if (dest_type instanceof ArrayType) {
				return new InstructionCP(Constants.CHECKCAST, cp.addArrayClass((ArrayType) dest_type));
			} else {
				return new InstructionCP(Constants.CHECKCAST, cp.addClass(((ObjectType) dest_type).getClassName()));
			}
		} else {
			throw new RuntimeException("Can not cast " + src_type + " to " + dest_type);
		}
	}

	public FieldInstruction createGetField(String class_name, String name, Type t) {
		return new FieldInstruction(Constants.GETFIELD, cp.addFieldref(class_name, name, t.getSignature()));
	}

	public FieldInstruction createGetStatic(String class_name, String name, Type t) {
		return new FieldInstruction(Constants.GETSTATIC, cp.addFieldref(class_name, name, t.getSignature()));
	}

	public FieldInstruction createPutField(String class_name, String name, Type t) {
		return new FieldInstruction(Constants.PUTFIELD, cp.addFieldref(class_name, name, t.getSignature()));
	}

	public FieldInstruction createPutStatic(String class_name, String name, Type t) {
		return new FieldInstruction(Constants.PUTSTATIC, cp.addFieldref(class_name, name, t.getSignature()));
	}

	public Instruction createCheckCast(ReferenceType t) {
		if (t instanceof ArrayType) {
			return new InstructionCP(Constants.CHECKCAST, cp.addArrayClass((ArrayType) t));
		} else {
			return new InstructionCP(Constants.CHECKCAST, cp.addClass((ObjectType) t));
		}
	}

	public Instruction createInstanceOf(ReferenceType t) {
		if (t instanceof ArrayType) {
			return new InstructionCP(Constants.INSTANCEOF, cp.addArrayClass((ArrayType) t));
		} else {
			return new InstructionCP(Constants.INSTANCEOF, cp.addClass((ObjectType) t));
		}
	}

	public Instruction createNew(ObjectType t) {
		return new InstructionCP(Constants.NEW, cp.addClass(t));
	}

	public Instruction createNew(String s) {
		return createNew(new ObjectType(s));
	}

	/**
	 * Create new array of given size and type.
	 *
	 * @return an instruction that creates the corresponding array at runtime, i.e. is an AllocationInstruction
	 */
	public Instruction createNewArray(Type t, short dim) {
		if (dim == 1) {
			if (t instanceof ObjectType) {
				return new InstructionCP(Constants.ANEWARRAY, cp.addClass((ObjectType) t));
			} else if (t instanceof ArrayType) {
				return new InstructionCP(Constants.ANEWARRAY, cp.addArrayClass((ArrayType) t));
			} else {
				return new InstructionByte(Constants.NEWARRAY, ((BasicType) t).getType());
			}
		} else {
			ArrayType at;

			if (t instanceof ArrayType) {
				at = (ArrayType) t;
			} else {
				at = new ArrayType(t, dim);
			}

			return new MULTIANEWARRAY(cp.addArrayClass(at), dim);
		}
	}

	/**
	 * Create "null" value for reference types, 0 for basic types like int
	 */
	public static Instruction createNull(Type type) {
		switch (type.getType()) {
		case Constants.T_ARRAY:
		case Constants.T_OBJECT:
			return ACONST_NULL;
		case Constants.T_INT:
		case Constants.T_SHORT:
		case Constants.T_BOOLEAN:
		case Constants.T_CHAR:
		case Constants.T_BYTE:
			return ICONST_0;
		case Constants.T_FLOAT:
			return FCONST_0;
		case Constants.T_DOUBLE:
			return DCONST_0;
		case Constants.T_LONG:
			return LCONST_0;
		case Constants.T_VOID:
			return NOP;

		default:
			throw new RuntimeException("Invalid type: " + type);
		}
	}

	/**
	 * Create branch instruction by given opcode, except LOOKUPSWITCH and TABLESWITCH. For those you should use the SWITCH compound
	 * instruction.
	 */
	public static InstructionBranch createBranchInstruction(short opcode, InstructionHandle target) {
		switch (opcode) {
		case Constants.IFEQ:
			return new InstructionBranch(Constants.IFEQ, target);
		case Constants.IFNE:
			return new InstructionBranch(Constants.IFNE, target);
		case Constants.IFLT:
			return new InstructionBranch(Constants.IFLT, target);
		case Constants.IFGE:
			return new InstructionBranch(Constants.IFGE, target);
		case Constants.IFGT:
			return new InstructionBranch(Constants.IFGT, target);
		case Constants.IFLE:
			return new InstructionBranch(Constants.IFLE, target);
		case Constants.IF_ICMPEQ:
			return new InstructionBranch(Constants.IF_ICMPEQ, target);
		case Constants.IF_ICMPNE:
			return new InstructionBranch(Constants.IF_ICMPNE, target);
		case Constants.IF_ICMPLT:
			return new InstructionBranch(Constants.IF_ICMPLT, target);
		case Constants.IF_ICMPGE:
			return new InstructionBranch(Constants.IF_ICMPGE, target);
		case Constants.IF_ICMPGT:
			return new InstructionBranch(Constants.IF_ICMPGT, target);
		case Constants.IF_ICMPLE:
			return new InstructionBranch(Constants.IF_ICMPLE, target);
		case Constants.IF_ACMPEQ:
			return new InstructionBranch(Constants.IF_ACMPEQ, target);
		case Constants.IF_ACMPNE:
			return new InstructionBranch(Constants.IF_ACMPNE, target);
		case Constants.GOTO:
			return new InstructionBranch(Constants.GOTO, target);
		case Constants.JSR:
			return new InstructionBranch(Constants.JSR, target);
		case Constants.IFNULL:
			return new InstructionBranch(Constants.IFNULL, target);
		case Constants.IFNONNULL:
			return new InstructionBranch(Constants.IFNONNULL, target);
		case Constants.GOTO_W:
			return new InstructionBranch(Constants.GOTO_W, target);
		case Constants.JSR_W:
			return new InstructionBranch(Constants.JSR_W, target);
		default:
			throw new RuntimeException("Invalid opcode: " + opcode);
		}
	}

	public void setClassGen(ClassGen c) {
		cg = c;
	}

	public ClassGen getClassGen() {
		return cg;
	}

	public void setConstantPool(ConstantPool c) {
		cp = c;
	}

	public ConstantPool getConstantPool() {
		return cp;
	}

	/**
	 * Returns the right instruction for putting whatever you want onto the stack
	 */
	public static Instruction PUSH(ConstantPool cp, int value) {
		Instruction instruction = null;
		if ((value >= -1) && (value <= 5)) {
			return INSTRUCTIONS[Constants.ICONST_0 + value];
		} else if ((value >= -128) && (value <= 127)) {
			instruction = new InstructionByte(Constants.BIPUSH, (byte) value);
		} else if ((value >= -32768) && (value <= 32767)) {
			instruction = new InstructionShort(Constants.SIPUSH, (short) value);
		} else // If everything fails create a Constant pool entry
		{
			int pos = cp.addInteger(value);
			if (pos <= Constants.MAX_BYTE) {
				instruction = new InstructionCP(Constants.LDC, pos);
			} else {
				instruction = new InstructionCP(Constants.LDC_W, pos);
			}
		}
		return instruction;
	}

	public static Instruction PUSH(ConstantPool cp, ObjectType t) {
		return new InstructionCP(Constants.LDC_W, cp.addClass(t));
	}

	public static Instruction PUSH(ConstantPool cp, boolean value) {
		return INSTRUCTIONS[Constants.ICONST_0 + (value ? 1 : 0)];
	}

	public static Instruction PUSH(ConstantPool cp, float value) {
		Instruction instruction = null;
		if (value == 0.0) {
			instruction = FCONST_0;
		} else if (value == 1.0) {
			instruction = FCONST_1;
		} else if (value == 2.0) {
			instruction = FCONST_2;
		} else {
			// Create a Constant pool entry
			int i = cp.addFloat(value);
			instruction = new InstructionCP(i <= Constants.MAX_BYTE ? Constants.LDC : Constants.LDC_W, i);
		}
		return instruction;
	}

	public static Instruction PUSH(ConstantPool cp, long value) {
		Instruction instruction = null;
		if (value == 0) {
			instruction = LCONST_0;
		} else if (value == 1) {
			instruction = LCONST_1;
		} else {
			instruction = new InstructionCP(Constants.LDC2_W, cp.addLong(value));
		}
		return instruction;
	}

	public static Instruction PUSH(ConstantPool cp, double value) {
		Instruction instruction = null;
		if (value == 0.0) {
			instruction = DCONST_0;
		} else if (value == 1.0) {
			instruction = DCONST_1;
		} else {
			// Create a Constant pool entry
			instruction = new InstructionCP(Constants.LDC2_W, cp.addDouble(value));
		}
		return instruction;
	}

	public static Instruction PUSH(ConstantPool cp, String value) {
		Instruction instruction = null;
		if (value == null) {
			instruction = ACONST_NULL;
		} else {
			int i = cp.addString(value);
			instruction = new InstructionCP(i <= Constants.MAX_BYTE ? Constants.LDC : Constants.LDC_W, i);
		}
		return instruction;
	}

	public static Instruction PUSH(ConstantPool cp, Number value) {
		Instruction instruction = null;
		if ((value instanceof Integer) || (value instanceof Short) || (value instanceof Byte)) {
			instruction = PUSH(cp, value.intValue());
		} else if (value instanceof Double) {
			instruction = PUSH(cp, value.doubleValue());
		} else if (value instanceof Float) {
			instruction = PUSH(cp, value.floatValue());
		} else if (value instanceof Long) {
			instruction = PUSH(cp, value.longValue());
		} else {
			throw new ClassGenException("What's this: " + value);
		}
		return instruction;
	}

	public static Instruction PUSH(ConstantPool cp, Character value) {
		return PUSH(cp, value.charValue());
	}

	public static Instruction PUSH(ConstantPool cp, Boolean value) {
		return PUSH(cp, value.booleanValue());
	}

	/**
	 * Return a list that will load the Class object - on 1.5 or later use the class variant of ldc, whilst on earlier JVMs use the
	 * regular Class.forName.
	 */
	public InstructionList PUSHCLASS(ConstantPool cp, String className) {
		InstructionList iList = new InstructionList();
		int classIndex = cp.addClass(className);
		if (cg != null && cg.getMajor() >= Constants.MAJOR_1_5) {
			if (classIndex <= Constants.MAX_BYTE) {
				iList.append(new InstructionCP(Instruction.LDC, classIndex));
			} else {
				iList.append(new InstructionCP(Instruction.LDC_W, classIndex));
			}
		} else {
			className = className.replace('/', '.');
			iList.append(InstructionFactory.PUSH(cp, className));
			iList.append(this.createInvoke("java.lang.Class", "forName", ObjectType.CLASS, Type.STRINGARRAY1,
					Constants.INVOKESTATIC));
		}
		return iList;
	}
}