/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.bcel.generic;
import org.apache.bcel.Constants;
/**
* 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 1598766 2014-05-30 22:51:27Z sebb $
* @author <A HREF="mailto:m.dahm@gmx.de">M. Dahm</A>
* @see Constants
*/
public class InstructionFactory implements InstructionConstants, java.io.Serializable {
private static final long serialVersionUID = -1210011499635580258L;
private static final String[] short_names = {
"C", "F", "D", "B", "S", "I", "L"
};
protected ClassGen cg;
protected ConstantPoolGen cp;
public InstructionFactory(ClassGen cg, ConstantPoolGen cp) {
this.cg = cg;
this.cp = cp;
}
/** Initialize with ClassGen object
*/
public InstructionFactory(ClassGen cg) {
this(cg, cg.getConstantPool());
}
/** Initialize just with ConstantPoolGen object
*/
public InstructionFactory(ConstantPoolGen cp) {
this(null, cp);
}
/** 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
* @see Constants
*/
public InvokeInstruction createInvoke( String class_name, String name, Type ret_type,
Type[] arg_types, short kind ) {
int index;
int nargs = 0;
String signature = Type.getMethodSignature(ret_type, arg_types);
for (Type arg_type : arg_types) {
nargs += arg_type.getSize();
}
if (kind == Constants.INVOKEINTERFACE) {
index = cp.addInterfaceMethodref(class_name, name, signature);
} else {
index = cp.addMethodref(class_name, name, signature);
}
switch (kind) {
case Constants.INVOKESPECIAL:
return new INVOKESPECIAL(index);
case Constants.INVOKEVIRTUAL:
return new INVOKEVIRTUAL(index);
case Constants.INVOKESTATIC:
return new INVOKESTATIC(index);
case Constants.INVOKEINTERFACE:
return new INVOKEINTERFACE(index, nargs + 1);
default:
throw new RuntimeException("Oops: Unknown invoke kind:" + kind);
}
}
/** Create a call to the most popular System.out.println() method.
*
* @param s the string to print
*/
public InstructionList createPrintln( String s ) {
InstructionList il = new InstructionList();
int out = cp.addFieldref("java.lang.System", "out", "Ljava/io/PrintStream;");
int println = cp.addMethodref("java.io.PrintStream", "println", "(Ljava/lang/String;)V");
il.append(new GETSTATIC(out));
il.append(new PUSH(cp, s));
il.append(new INVOKEVIRTUAL(println));
return il;
}
/** Uses PUSH to push a constant value onto the stack.
* @param value must be of type Number, Boolean, Character or String
*/
public Instruction createConstant( Object value ) {
PUSH push;
if (value instanceof Number) {
push = new PUSH(cp, (Number) value);
} else if (value instanceof String) {
push = new PUSH(cp, (String) value);
} else if (value instanceof Boolean) {
push = new PUSH(cp, (Boolean) value);
} else if (value instanceof Character) {
push = new PUSH(cp, (Character) value);
} else {
throw new ClassGenException("Illegal type: " + value.getClass());
}
return push.getInstruction();
}
private static class MethodObject {
Type[] arg_types;
Type result_type;
String class_name;
String name;
MethodObject(String c, String n, Type r, Type[] a) {
class_name = c;
name = n;
result_type = r;
arg_types = a;
}
}
private InvokeInstruction createInvoke( MethodObject m, short kind ) {
return createInvoke(m.class_name, m.name, m.result_type, m.arg_types, kind);
}
private static final MethodObject[] append_mos = {
new MethodObject("java.lang.StringBuffer", "append", Type.STRINGBUFFER, new Type[] {
Type.STRING
}),
new MethodObject("java.lang.StringBuffer", "append", Type.STRINGBUFFER, new Type[] {
Type.OBJECT
}),
null,
null, // indices 2, 3
new MethodObject("java.lang.StringBuffer", "append", Type.STRINGBUFFER, new Type[] {
Type.BOOLEAN
}),
new MethodObject("java.lang.StringBuffer", "append", Type.STRINGBUFFER, new Type[] {
Type.CHAR
}),
new MethodObject("java.lang.StringBuffer", "append", Type.STRINGBUFFER, new Type[] {
Type.FLOAT
}),
new MethodObject("java.lang.StringBuffer", "append", Type.STRINGBUFFER, new Type[] {
Type.DOUBLE
}),
new MethodObject("java.lang.StringBuffer", "append", Type.STRINGBUFFER, new Type[] {
Type.INT
}),
new MethodObject("java.lang.StringBuffer", "append", Type.STRINGBUFFER, // No append(byte)
new Type[] {
Type.INT
}),
new MethodObject("java.lang.StringBuffer", "append", Type.STRINGBUFFER, // No append(short)
new Type[] {
Type.INT
}),
new MethodObject("java.lang.StringBuffer", "append", Type.STRINGBUFFER, new Type[] {
Type.LONG
})
};
private static boolean isString( Type type ) {
return ((type instanceof ObjectType) && ((ObjectType) type).getClassName().equals(
"java.lang.String"));
}
public Instruction createAppend( Type type ) {
byte t = type.getType();
if (isString(type)) {
return createInvoke(append_mos[0], Constants.INVOKEVIRTUAL);
}
switch (t) {
case Constants.T_BOOLEAN:
case Constants.T_CHAR:
case Constants.T_FLOAT:
case Constants.T_DOUBLE:
case Constants.T_BYTE:
case Constants.T_SHORT:
case Constants.T_INT:
case Constants.T_LONG:
return createInvoke(append_mos[t], Constants.INVOKEVIRTUAL);
case Constants.T_ARRAY:
case Constants.T_OBJECT:
return createInvoke(append_mos[1], Constants.INVOKEVIRTUAL);
default:
throw new RuntimeException("Oops: No append for this type? " + type);
}
}
/** 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 GETFIELD(index);
case Constants.PUTFIELD:
return new PUTFIELD(index);
case Constants.GETSTATIC:
return new GETSTATIC(index);
case Constants.PUTSTATIC:
return new PUTSTATIC(index);
default:
throw new RuntimeException("Oops: Unknown getfield kind:" + kind);
}
}
/** Create reference to `this'
*/
public static Instruction createThis() {
return new ALOAD(0);
}
/** Create typed return
*/
public static ReturnInstruction 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);
}
}
private static ArithmeticInstruction createBinaryIntOp( char first, String op ) {
switch (first) {
case '-':
return ISUB;
case '+':
return IADD;
case '%':
return IREM;
case '*':
return IMUL;
case '/':
return IDIV;
case '&':
return IAND;
case '|':
return IOR;
case '^':
return IXOR;
case '<':
return ISHL;
case '>':
return op.equals(">>>")
? (ArithmeticInstruction) IUSHR
: (ArithmeticInstruction) ISHR;
default:
throw new RuntimeException("Invalid operand " + op);
}
}
private static ArithmeticInstruction createBinaryLongOp( char first, String op ) {
switch (first) {
case '-':
return LSUB;
case '+':
return LADD;
case '%':
return LREM;
case '*':
return LMUL;
case '/':
return LDIV;
case '&':
return LAND;
case '|':
return LOR;
case '^':
return LXOR;
case '<':
return LSHL;
case '>':
return op.equals(">>>")
? (ArithmeticInstruction) LUSHR
: (ArithmeticInstruction) LSHR;
default:
throw new RuntimeException("Invalid operand " + op);
}
}
private static ArithmeticInstruction createBinaryFloatOp( char op ) {
switch (op) {
case '-':
return FSUB;
case '+':
return FADD;
case '*':
return FMUL;
case '/':
return FDIV;
case '%':
return FREM;
default:
throw new RuntimeException("Invalid operand " + op);
}
}
private static ArithmeticInstruction createBinaryDoubleOp( char op ) {
switch (op) {
case '-':
return DSUB;
case '+':
return DADD;
case '*':
return DMUL;
case '/':
return DDIV;
case '%':
return DREM;
default:
throw new RuntimeException("Invalid operand " + op);
}
}
/**
* Create binary operation for simple basic types, such as int and float.
*
* @param op operation, such as "+", "*", "<<", etc.
*/
public static ArithmeticInstruction createBinaryOperation( String op, Type type ) {
char first = op.toCharArray()[0];
switch (type.getType()) {
case Constants.T_BYTE:
case Constants.T_SHORT:
case Constants.T_INT:
case Constants.T_CHAR:
return createBinaryIntOp(first, op);
case Constants.T_LONG:
return createBinaryLongOp(first, op);
case Constants.T_FLOAT:
return createBinaryFloatOp(first);
case Constants.T_DOUBLE:
return createBinaryDoubleOp(first);
default:
throw new RuntimeException("Invalid type " + type);
}
}
/**
* @param size size of operand, either 1 (int, e.g.) or 2 (double)
*/
public static StackInstruction createPop( int size ) {
return (size == 2) ? (StackInstruction) POP2 : (StackInstruction) POP;
}
/**
* @param size size of operand, either 1 (int, e.g.) or 2 (double)
*/
public static StackInstruction createDup( int size ) {
return (size == 2) ? (StackInstruction) DUP2 : (StackInstruction) DUP;
}
/**
* @param size size of operand, either 1 (int, e.g.) or 2 (double)
*/
public static StackInstruction createDup_2( int size ) {
return (size == 2) ? (StackInstruction) DUP2_X2 : (StackInstruction) DUP_X2;
}
/**
* @param size size of operand, either 1 (int, e.g.) or 2 (double)
*/
public static StackInstruction createDup_1( int size ) {
return (size == 2) ? (StackInstruction) DUP2_X1 : (StackInstruction) DUP_X1;
}
/**
* @param index index of local variable
*/
public static LocalVariableInstruction 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 ISTORE(index);
case Constants.T_FLOAT:
return new FSTORE(index);
case Constants.T_DOUBLE:
return new DSTORE(index);
case Constants.T_LONG:
return new LSTORE(index);
case Constants.T_ARRAY:
case Constants.T_OBJECT:
return new ASTORE(index);
default:
throw new RuntimeException("Invalid type " + type);
}
}
/**
* @param index index of local variable
*/
public static LocalVariableInstruction 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 ILOAD(index);
case Constants.T_FLOAT:
return new FLOAD(index);
case Constants.T_DOUBLE:
return new DLOAD(index);
case Constants.T_LONG:
return new LLOAD(index);
case Constants.T_ARRAY:
case Constants.T_OBJECT:
return new ALOAD(index);
default:
throw new RuntimeException("Invalid type " + type);
}
}
/**
* @param type type of elements of array, i.e., array.getElementType()
*/
public static ArrayInstruction 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 ArrayInstruction 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);
}
}
/** 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;
}
String name = "org.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, e);
}
return i;
} else if ((src_type instanceof ReferenceType) && (dest_type instanceof ReferenceType)) {
if (dest_type instanceof ArrayType) {
return new CHECKCAST(cp.addArrayClass((ArrayType) dest_type));
} else {
return new CHECKCAST(cp.addClass(((ObjectType) dest_type).getClassName()));
}
} else {
throw new RuntimeException("Can not cast " + src_type + " to " + dest_type);
}
}
public GETFIELD createGetField( String class_name, String name, Type t ) {
return new GETFIELD(cp.addFieldref(class_name, name, t.getSignature()));
}
public GETSTATIC createGetStatic( String class_name, String name, Type t ) {
return new GETSTATIC(cp.addFieldref(class_name, name, t.getSignature()));
}
public PUTFIELD createPutField( String class_name, String name, Type t ) {
return new PUTFIELD(cp.addFieldref(class_name, name, t.getSignature()));
}
public PUTSTATIC createPutStatic( String class_name, String name, Type t ) {
return new PUTSTATIC(cp.addFieldref(class_name, name, t.getSignature()));
}
public CHECKCAST createCheckCast( ReferenceType t ) {
if (t instanceof ArrayType) {
return new CHECKCAST(cp.addArrayClass((ArrayType) t));
} else {
return new CHECKCAST(cp.addClass((ObjectType) t));
}
}
public INSTANCEOF createInstanceOf( ReferenceType t ) {
if (t instanceof ArrayType) {
return new INSTANCEOF(cp.addArrayClass((ArrayType) t));
} else {
return new INSTANCEOF(cp.addClass((ObjectType) t));
}
}
public NEW createNew( ObjectType t ) {
return new NEW(cp.addClass(t));
}
public NEW createNew( String s ) {
return createNew(ObjectType.getInstance(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 ANEWARRAY(cp.addClass((ObjectType) t));
} else if (t instanceof ArrayType) {
return new ANEWARRAY(cp.addArrayClass((ArrayType) t));
} else {
return new 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 BranchInstruction createBranchInstruction( short opcode, InstructionHandle target ) {
switch (opcode) {
case Constants.IFEQ:
return new IFEQ(target);
case Constants.IFNE:
return new IFNE(target);
case Constants.IFLT:
return new IFLT(target);
case Constants.IFGE:
return new IFGE(target);
case Constants.IFGT:
return new IFGT(target);
case Constants.IFLE:
return new IFLE(target);
case Constants.IF_ICMPEQ:
return new IF_ICMPEQ(target);
case Constants.IF_ICMPNE:
return new IF_ICMPNE(target);
case Constants.IF_ICMPLT:
return new IF_ICMPLT(target);
case Constants.IF_ICMPGE:
return new IF_ICMPGE(target);
case Constants.IF_ICMPGT:
return new IF_ICMPGT(target);
case Constants.IF_ICMPLE:
return new IF_ICMPLE(target);
case Constants.IF_ACMPEQ:
return new IF_ACMPEQ(target);
case Constants.IF_ACMPNE:
return new IF_ACMPNE(target);
case Constants.GOTO:
return new GOTO(target);
case Constants.JSR:
return new JSR(target);
case Constants.IFNULL:
return new IFNULL(target);
case Constants.IFNONNULL:
return new IFNONNULL(target);
case Constants.GOTO_W:
return new GOTO_W(target);
case Constants.JSR_W:
return new 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( ConstantPoolGen c ) {
cp = c;
}
public ConstantPoolGen getConstantPool() {
return cp;
}
}