/*
* Copyright 2014, The Sporting Exchange Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.betfair.cougar.marshalling.impl.util;
import org.apache.bcel.generic.*;
import org.apache.bcel.classfile.*;
import org.apache.bcel.*;
import java.io.*;
public class EnumCreator implements Constants {
private final String enumType ;
private InstructionFactory _factory;
private ConstantPoolGen _cp;
private ClassGen _cg;
private String[] enums;
public EnumCreator(String enumType, String[] enums) {
_cg = new ClassGen(enumType, "java.lang.Enum", "EnumOperationHeaderParamEnum.java", ACC_PUBLIC | ACC_FINAL | ACC_SUPER | ACC_ENUM, new String[] { });
_cg.setMajor(50);
_cg.setMinor(0);
_cp = _cg.getConstantPool();
_factory = new InstructionFactory(_cg, _cp);
this.enumType = enumType;
this.enums = enums;
}
public void create(OutputStream out) throws IOException {
createFields();
createMethod_0();
createMethod_1();
createMethod_2();
createMethod_3();
_cg.getJavaClass().dump(out);
}
private void createFields() {
FieldGen field;
for (String anEnum : enums) {
field = new FieldGen(ACC_PUBLIC | ACC_STATIC | ACC_FINAL | ACC_ENUM, new ObjectType(enumType), anEnum, _cp);
_cg.addField(field.getField());
}
field = new FieldGen(ACC_PRIVATE | ACC_STATIC | ACC_FINAL | ACC_SYNTHETIC, new ArrayType(new ObjectType(enumType), 1), "ENUM$VALUES", _cp);
_cg.addField(field.getField());
}
private void createMethod_0() {
InstructionList il = new InstructionList();
MethodGen method = new MethodGen(ACC_STATIC, Type.VOID, Type.NO_ARGS, new String[] { }, "<clinit>", enumType, il, _cp);
int code = 0;
for (String anEnum : enums) {
InstructionHandle ih_0 = il.append(_factory.createNew(enumType));
il.append(InstructionConstants.DUP);
il.append(new PUSH(_cp, anEnum));
il.append(new PUSH(_cp, code++));
il.append(_factory.createInvoke(enumType, "<init>", Type.VOID, new Type[] { Type.STRING, Type.INT }, Constants.INVOKESPECIAL));
il.append(_factory.createFieldAccess(enumType, anEnum, new ObjectType(enumType), Constants.PUTSTATIC));
}
InstructionHandle ih_39 = il.append(new PUSH(_cp, enums.length));
il.append(_factory.createNewArray(new ObjectType(enumType), (short) 1));
code =0;
for (String anEnum : enums) {
il.append(InstructionConstants.DUP);
il.append(new PUSH(_cp, code++));
il.append(_factory.createFieldAccess(enumType, anEnum, new ObjectType(enumType), Constants.GETSTATIC));
il.append(InstructionConstants.AASTORE);
}
il.append(_factory.createFieldAccess(enumType, "ENUM$VALUES", new ArrayType(new ObjectType(enumType), 1), Constants.PUTSTATIC));
il.append(_factory.createReturn(Type.VOID));
method.setMaxStack();
method.setMaxLocals();
_cg.addMethod(method.getMethod());
il.dispose();
}
private void createMethod_1() {
InstructionList il = new InstructionList();
MethodGen method = new MethodGen(ACC_PRIVATE, Type.VOID, new Type[] { Type.STRING, Type.INT }, new String[] { "arg0", "arg1" }, "<init>", enumType, il, _cp);
InstructionHandle ih_0 = il.append(_factory.createLoad(Type.OBJECT, 0));
il.append(_factory.createLoad(Type.OBJECT, 1));
il.append(_factory.createLoad(Type.INT, 2));
il.append(_factory.createInvoke("java.lang.Enum", "<init>", Type.VOID, new Type[] { Type.STRING, Type.INT }, Constants.INVOKESPECIAL));
InstructionHandle ih_6 = il.append(_factory.createReturn(Type.VOID));
method.setMaxStack();
method.setMaxLocals();
_cg.addMethod(method.getMethod());
il.dispose();
}
private void createMethod_2() {
InstructionList il = new InstructionList();
MethodGen method = new MethodGen(ACC_PUBLIC | ACC_STATIC, new ArrayType(new ObjectType(enumType), 1), Type.NO_ARGS, new String[] { }, "values", enumType, il, _cp);
InstructionHandle ih_0 = il.append(_factory.createFieldAccess(enumType, "ENUM$VALUES", new ArrayType(new ObjectType(enumType), 1), Constants.GETSTATIC));
il.append(InstructionConstants.DUP);
il.append(_factory.createStore(Type.OBJECT, 0));
il.append(new PUSH(_cp, 0));
il.append(_factory.createLoad(Type.OBJECT, 0));
il.append(InstructionConstants.ARRAYLENGTH);
il.append(InstructionConstants.DUP);
il.append(_factory.createStore(Type.INT, 1));
il.append(_factory.createNewArray(new ObjectType(enumType), (short) 1));
il.append(InstructionConstants.DUP);
il.append(_factory.createStore(Type.OBJECT, 2));
il.append(new PUSH(_cp, 0));
il.append(_factory.createLoad(Type.INT, 1));
il.append(_factory.createInvoke("java.lang.System", "arraycopy", Type.VOID, new Type[] { Type.OBJECT, Type.INT, Type.OBJECT, Type.INT, Type.INT }, Constants.INVOKESTATIC));
il.append(_factory.createLoad(Type.OBJECT, 2));
il.append(_factory.createReturn(Type.OBJECT));
method.setMaxStack();
method.setMaxLocals();
_cg.addMethod(method.getMethod());
il.dispose();
}
private void createMethod_3() {
InstructionList il = new InstructionList();
MethodGen method = new MethodGen(ACC_PUBLIC | ACC_STATIC, new ObjectType(enumType), new Type[] { Type.STRING }, new String[] { "arg0" }, "valueOf", enumType, il, _cp);
InstructionHandle ih_0 = il.append(new LDC(4));
il.append(_factory.createLoad(Type.OBJECT, 0));
il.append(_factory.createInvoke("java.lang.Enum", "valueOf", new ObjectType("java.lang.Enum"), new Type[] { new ObjectType("java.lang.Class"), Type.STRING }, Constants.INVOKESTATIC));
il.append(_factory.createCheckCast(new ObjectType(enumType)));
InstructionHandle ih_9 = il.append(_factory.createReturn(Type.OBJECT));
method.setMaxStack();
method.setMaxLocals();
_cg.addMethod(method.getMethod());
il.dispose();
}
}