--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/com/go/trove/classfile/CodeAssembler.java	Sat Mar 21 11:00:06 2009 +0000
@@ -0,0 +1,664 @@
+/* ====================================================================
+ * Trove - Copyright (c) 1997-2000 Walt Disney Internet Group
+ * ====================================================================
+ * The Tea Software License, Version 1.1
+ *
+ * Copyright (c) 2000 Walt Disney Internet Group. 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
+ *        Walt Disney Internet Group (http://opensource.go.com/)."
+ *    Alternately, this acknowledgment may appear in the software itself,
+ *    if and wherever such third-party acknowledgments normally appear.
+ *
+ * 4. The names "Tea", "TeaServlet", "Kettle", "Trove" and "BeanDoc" must
+ *    not be used to endorse or promote products derived from this
+ *    software without prior written permission. For written
+ *    permission, please contact opensource@dig.com.
+ *
+ * 5. Products derived from this software may not be called "Tea",
+ *    "TeaServlet", "Kettle" or "Trove", nor may "Tea", "TeaServlet",
+ *    "Kettle", "Trove" or "BeanDoc" appear in their name, without prior
+ *    written permission of the Walt Disney Internet Group.
+ *
+ * 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 WALT DISNEY INTERNET GROUP 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.
+ * ====================================================================
+ *
+ * For more information about Tea, please see http://opensource.go.com/.
+ */
+
+package com.go.trove.classfile;
+
+/******************************************************************************
+ * CodeAssembler is a high-level interface for assembling Java Virtual Machine
+ * byte code. It can also be used as a visitor to a disassembler.
+ *
+ * @author Brian S O'Neill
+ * @version
+ * <!--$$Revision: 1.1 $-->, <!--$$JustDate:-->  9/07/00 <!-- $-->
+ */
+public interface CodeAssembler {
+    /**
+     * Returns LocalVariable references for all the parameters passed into
+     * the method being assembled, not including any "this" reference.
+     * Returns a zero-length array if there are no passed in parameters.
+     *
+     * <p>The names of the LocalVariables returned by this method are initially
+     * set to null. It is encouraged that a name be provided.
+     */
+    public LocalVariable[] getParameters();
+
+    /**
+     * Creates a LocalVariable reference from a name and type. Although name
+     * is optional, it is encouraged that a name be provided. Names do not 
+     * need to be unique.
+     *
+     * @param name Optional name for the LocalVariable.
+     * @param type The type of data that the requested LocalVariable can 
+     * store. 
+     */
+    public LocalVariable createLocalVariable(String name, 
+                                             TypeDescriptor type);
+
+    /**
+     * Creates a label, whose location must be set. To create a label and
+     * locate it here, the following example demonstrates how the call to
+     * setLocation can be chained:
+     *
+     * <pre>
+     * CodeBuilder builder;
+     * ...
+     * Label label = builder.createLabel().setLocation();
+     * </pre>
+     *
+     * @see Label#setLocation
+     */ 
+    public Label createLabel();
+
+    /**
+     * Sets up an exception handler located here, the location of the next
+     * code to be generated.
+     *
+     * @param startLocation Location at the start of the section of
+     * code to be wrapped by an exception handler.
+     * @param endLocation Location directly after the end of the
+     * section of code.
+     * @param catchClassName The name of the type of exception to be caught; 
+     * if null, then catch every object.
+     */
+    public void exceptionHandler(Location startLocation,
+                                 Location endLocation,
+                                 String catchClassName);
+    
+    /**
+     * Map the location of the next code to be generated to a line number 
+     * in source code. This enables line numbers in a stack trace from the 
+     * generated code.
+     */
+    public void mapLineNumber(int lineNumber);
+
+    // load-constant-to-stack style instructions
+
+    /**
+     * Generates code that loads a constant string value onto the stack.
+     * If value is null, the generated code loads a null onto the stack.
+     * Strings that exceed 65535 UTF encoded bytes in length are loaded by
+     * creating a StringBuffer, appending substrings, and then converting to a
+     * String.
+     */
+    public void loadConstant(String value);
+
+    /**
+     * Generates code that loads a constant boolean value onto the stack.
+     */
+    public void loadConstant(boolean value);
+
+    /**
+     * Generates code that loads a constant int, char, short or byte value 
+     * onto the stack.
+     */
+    public void loadConstant(int value);
+
+    /**
+     * Generates code that loads a constant long value onto the stack.
+     */
+    public void loadConstant(long value);
+
+    /**
+     * Generates code that loads a constant float value onto the stack.
+     */
+    public void loadConstant(float value);
+
+    /**
+     * Generates code that loads a constant double value onto the stack.
+     */
+    public void loadConstant(double value);
+
+    // load-local-to-stack style instructions
+
+    /**
+     * Generates code that loads a local variable onto the stack. Parameters
+     * passed to a method and the "this" reference are all considered local
+     * variables, as well as any that were created.
+     *
+     * @param local The local variable reference
+     */
+    public void loadLocal(LocalVariable local);
+
+    /**
+     * Loads a reference to "this" onto the stack. Static methods have no 
+     * "this" reference, and an exception is thrown when attempting to
+     * generate "this" in a static method.
+     */
+    public void loadThis();
+
+    // store-from-stack-to-local style instructions
+
+    /**
+     * Generates code that pops a value off of the stack into a local variable.
+     * Parameters passed to a method and the "this" reference are all 
+     * considered local variables, as well as any that were created.
+     *
+     * @param local The local variable reference
+     */
+    public void storeLocal(LocalVariable local);
+
+    // load-to-stack-from-array style instructions
+
+    /**
+     * Generates code that loads a value from an array. An array
+     * reference followed by an index must be on the stack. The array 
+     * reference and index are replaced by the value retrieved from the array 
+     * after the generated instruction has executed.
+     *
+     * <p>The type doesn't need to be an exact match for objects. Object.class
+     * works fine for all objects. For primitive types, use the class that
+     * matches that type. For an int the type is int.class.
+     *
+     * @param type The type of data stored in the array.
+     */
+    public void loadFromArray(Class type);
+
+    // store-to-array-from-stack style instructions
+
+    /**
+     * Generates code that stores a value to an array. An array
+     * reference followed by an index, followed by a value (or two if a long
+     * or double) must be on the stack. All items on the stack are gone
+     * after the generated instruction has executed.
+     *
+     * <p>The type doesn't need to be an exact match for objects. Object.class
+     * works fine for all objects. For primitive types, use the class that
+     * matches that type. For an int the type is int.class.
+     *
+     * @param type The type of data stored in the array.
+     */
+    public void storeToArray(Class type);
+
+    // load-field-to-stack style instructions
+
+    /**
+     * Generates code that loads a value from a field from this class. 
+     * An object reference must be on the stack. After the generated code 
+     * has executed, the object reference is replaced by the value retrieved 
+     * from the field.
+     */
+    public void loadField(String fieldName,
+                          TypeDescriptor type);
+
+    /**
+     * Generates code that loads a value from a field from any class. 
+     * An object reference must be on the stack. After the generated code 
+     * has executed, the object reference is replaced by the value retrieved 
+     * from the field.
+     */
+    public void loadField(String className,
+                          String fieldName,
+                          TypeDescriptor type);
+
+    /**
+     * Generates code that loads a value from a static field from this class. 
+     * After the generated code has executed, the value retrieved is placed
+     * on the stack.
+     */
+    public void loadStaticField(String fieldName,
+                                TypeDescriptor type);
+
+    /**
+     * Generates code that loads a value from a static field from any class. 
+     * After the generated code has executed, the value retrieved is placed
+     * on the stack.
+     */
+    public void loadStaticField(String className,
+                                String fieldName,
+                                TypeDescriptor type);
+
+    // store-to-field-from-stack style instructions
+
+    /**
+     * Generates code that stores a value into a field from this class. 
+     * An object reference and value must be on the stack. After the generated 
+     * code has executed, the object reference and value are gone from
+     * the stack.
+     */
+    public void storeField(String fieldName,
+                           TypeDescriptor type);
+
+    /**
+     * Generates code that stores a value into a field from any class. 
+     * An object reference and value must be on the stack. After the generated 
+     * code has executed, the object reference and value are gone from
+     * the stack.
+     */
+    public void storeField(String className,
+                           String fieldName,
+                           TypeDescriptor type);
+
+    /**
+     * Generates code that stores a value into a field from this class. 
+     * A value must be on the stack. After the generated 
+     * code has executed, the value is gone from the stack.
+     */
+    public void storeStaticField(String fieldName,
+                                 TypeDescriptor type);
+
+    /**
+     * Generates code that stores a value into a field from any class. 
+     * A value must be on the stack. After the generated 
+     * code has executed, the value is gone from the stack.
+     */
+    public void storeStaticField(String className,
+                                 String fieldName,
+                                 TypeDescriptor type);
+
+    // return style instructions
+
+    /**
+     * Generates code that returns void.
+     */
+    public void returnVoid();
+
+    /**
+     * Generates code that returns an object or primitive type. The value to
+     * return must be on the stack.
+     *
+     * <p>The type doesn't need to be an exact match for objects. Object.class
+     * works fine for all objects. For primitive types, use the class that
+     * matches that type. For an int the type is int.class.
+     */
+    public void returnValue(Class type);
+
+    // numerical conversion style instructions
+
+    /**
+     * Generates code that converts the value of a primitive type already
+     * on the stack.
+     */
+    public void convert(Class fromType, Class toType);
+
+    // invocation style instructions
+
+    /**
+     * Generates code to invoke a virtual method in this class. The object
+     * reference and the method's argument(s) must be on the stack.
+     *
+     * @param ret May be null if method returns void.
+     * @param params May be null if method takes no parameters.
+     */
+    public void invokeVirtual(String methodName,
+                              TypeDescriptor ret,
+                              TypeDescriptor[] params);
+
+    /**
+     * Generates code to invoke a virtual method in any class. The object
+     * reference and the method's argument(s) must be on the stack.
+     *
+     * @param ret May be null if method returns void.
+     * @param params May be null if method takes no parameters.
+     */
+    public void invokeVirtual(String className,
+                              String methodName,
+                              TypeDescriptor ret,
+                              TypeDescriptor[] params);
+
+    /**
+     * Generates code to invoke a static method in this class. The method's
+     * argument(s) must be on the stack.
+     *
+     * @param ret May be null if method returns void.
+     * @param params May be null if method takes no parameters.
+     */
+    public void invokeStatic(String methodName,
+                             TypeDescriptor ret,
+                             TypeDescriptor[] params);
+
+    /**
+     * Generates code to invoke a static method in any class. The method's
+     * argument(s) must be on the stack.
+     *
+     * @param ret May be null if method returns void.
+     * @param params May be null if method takes no parameters.
+     */
+    public void invokeStatic(String className,
+                             String methodName,
+                             TypeDescriptor ret,
+                             TypeDescriptor[] params);
+
+    /**
+     * Generates code to invoke an interface method in any class. The object
+     * reference and the method's argument(s) must be on the stack.
+     *
+     * @param ret May be null if method returns void.
+     * @param params May be null if method takes no parameters.
+     */
+    public void invokeInterface(String className,
+                                String methodName,
+                                TypeDescriptor ret,
+                                TypeDescriptor[] params);
+
+    /**
+     * Generates code to invoke a private method in this class.
+     * The object reference and the method's argument(s) must be on the stack.
+     *
+     * @param ret May be null if method returns void.
+     * @param params May be null if method takes no parameters.
+     */
+    public void invokePrivate(String methodName,
+                              TypeDescriptor ret,
+                              TypeDescriptor[] params);
+
+    /**
+     * Generates code to invoke a method in the super class.
+     * The object reference and the method's argument(s) must be on the stack.
+     *
+     * @param ret May be null if method returns void.
+     * @param params May be null if method takes no parameters.
+     */
+    public void invokeSuper(String superClassName,
+                            String methodName,
+                            TypeDescriptor ret,
+                            TypeDescriptor[] params);
+
+    /**
+     * Generates code to invoke a class constructor in this class. The object 
+     * reference and the constructor's argument(s) must be on the stack.
+     *
+     * @param params May be null if constructor takes no parameters.
+     */
+    public void invokeConstructor(TypeDescriptor[] params);
+
+    /**
+     * Generates code to invoke a class constructor in any class. The object 
+     * reference and the constructor's argument(s) must be on the stack.
+     *
+     * @param params May be null if constructor takes no parameters.
+     */
+    public void invokeConstructor(String className, TypeDescriptor[] params);
+
+    /**
+     * Generates code to invoke a super class constructor. The object 
+     * reference and the constructor's argument(s) must be on the stack.
+     *
+     * @param params May be null if constructor takes no parameters.
+     */
+    public void invokeSuperConstructor(TypeDescriptor[] params);
+
+    // creation style instructions
+
+    /**
+     * Generates code to create a new object. Unless the new object is an 
+     * array, it is invalid until a constructor method is invoked on it.
+     * When creating arrays, the size for each dimension must be on the
+     * operand stack.
+     *
+     * @see #invokeConstructor
+     */
+    public void newObject(TypeDescriptor type);
+
+    // stack operation style instructions
+
+    /**
+     * Generates code for the dup instruction.
+     */
+    public void dup();
+
+    /**
+     * Generates code for the dup_x1 instruction.
+     */
+    public void dupX1();
+
+    /**
+     * Generates code for the dup_x2 instruction.
+     */
+    public void dupX2();
+
+    /**
+     * Generates code for the dup2 instruction.
+     */
+    public void dup2();
+
+    /**
+     * Generates code for the dup2_x1 instruction.
+     */
+    public void dup2X1();
+
+    /**
+     * Generates code for the dup2_x2 instruction.
+     */
+    public void dup2X2();
+
+    /**
+     * Generates code for the pop instruction.
+     */
+    public void pop();
+
+    /**
+     * Generates code for the pop2 instruction.
+     */
+    public void pop2();
+
+    /**
+     * Generates code for the swap instruction.
+     */
+    public void swap();
+
+    /**
+     * Generates code for a swap2 instruction.
+     */
+    public void swap2();
+
+    // flow control instructions
+
+    /**
+     * Generates code that performs an unconditional branch to the specified
+     * location.
+     *
+     * @param location The location to branch to
+     */
+    public void branch(Location location);
+
+    /**
+     * Generates code that performs a conditional branch based on the
+     * value of an object on the stack. A branch is performed based on whether
+     * the object reference on the stack is null or not.
+     *
+     * @param location The location to branch to
+     * @param choice If true, do branch when null, else branch when not null
+     */
+    public void ifNullBranch(Location location, boolean choice);
+
+    /**
+     * Generates code that performs a conditional branch based on the value of
+     * two object references on the stack. A branch is performed based on
+     * whether the two objects are equal.
+     *
+     * @param location The location to branch to
+     * @param choice If true, branch when equal, else branch when not equal
+     */
+    public void ifEqualBranch(Location location, boolean choice);
+
+    /**
+     * Generates code the performs a conditional branch based on a comparison
+     * between an int value on the stack and zero. The int value on the
+     * stack is on the left side of the comparison expression.
+     *
+     * @param location The location to branch to
+     * @param choice One of "==", "!=", "<", ">=", ">" or "<="
+     * @exception IllegalArgumentException When the choice is not valid
+     */
+    public void ifZeroComparisonBranch(Location location, String choice) 
+        throws IllegalArgumentException;
+
+    /**
+     * Generates code the performs a conditional branch based on a comparison
+     * between two int values on the stack. The first int value on the stack
+     * is on the left side of the comparison expression.
+     *
+     * @param location The location to branch to
+     * @param choice One of "==", "!=", "<", ">=", ">" or "<="
+     * @exception IllegalArgumentException When the choice is not valid
+     */
+    public void ifComparisonBranch(Location location, String choice)
+        throws IllegalArgumentException;
+
+    /**
+     * Generates code for a switch statement. The generated code is either a
+     * lookupswitch or tableswitch. The choice of which switch type to generate
+     * is made based on the amount of bytes to be generated. A tableswitch
+     * is usually smaller, unless the cases are sparse.
+     *
+     * <p>The key value to switch on must already be on the stack when this
+     * instruction executes.
+     *
+     * @param cases The values to match on. The array length must be the same
+     * as for locations.
+     * @param locations The locations to branch to for each case.
+     * The array length must be the same as for cases.
+     * @param defaultLocation The location to branch to if the key on
+     * the stack was not matched.
+     */
+    public void switchBranch(int[] cases, 
+                             Location[] locations, Location defaultLocation);
+
+    /**
+     * Generates code that performs a subroutine branch to the specified 
+     * location. The instruction generated is either jsr or jsr_w. It is most
+     * often used for implementing a finally block.
+     *
+     * @param Location The location to branch to
+     */
+    public void jsr(Location location);
+
+    /**
+     * Generates code that returns from a subroutine invoked by jsr.
+     *
+     * @param local The local variable reference that contains the return
+     * address. The local variable must be of an object type.
+     */
+    public void ret(LocalVariable local);
+
+    // math instructions
+
+    /**
+     * Generates code for either a unary or binary math operation on one
+     * or two values pushed on the stack.
+     *
+     * <p>Pass in an opcode from the the Opcode class. The only valid math
+     * opcodes are:
+     *
+     * <pre>
+     * IADD, ISUB, IMUL, IDIV, IREM, INEG, IAND, IOR, IXOR, ISHL, ISHR, IUSHR
+     * LADD, LSUB, LMUL, LDIV, LREM, LNEG, LAND, LOR, LXOR, LSHL, LSHR, LUSHR
+     * FADD, FSUB, FMUL, FDIV, FREM, FNEG
+     * DADD, DSUB, DMUL, DDIV, DREM, DNEG
+     *
+     * LCMP
+     * FCMPG, FCMPL
+     * DCMPG, DCMPL
+     * </pre>
+     *
+     * A not operation (~) is performed by doing a loadConstant with either
+     * -1 or -1L followed by math(Opcode.IXOR) or math(Opcode.LXOR).
+     *
+     * @param opcode An opcode from the Opcode class.
+     * @exception IllegalArgumentException When the opcode selected is not
+     * a math operation.
+     * @see Opcode
+     */
+    public void math(byte opcode);
+
+    // miscellaneous instructions
+
+    /**
+     * Generates code for an arraylength instruction. The object to get the
+     * length from must already be on the stack.
+     */
+    public void arrayLength();
+
+    /**
+     * Generates code that throws an exception. The object to throw must
+     * already be on the stack.
+     */
+    public void throwObject();
+
+    /**
+     * Generates code that performs an object cast operation. The object
+     * to check must already be on the stack.
+     */
+    public void checkCast(TypeDescriptor type);
+
+    /**
+     * Generates code that performs an instanceof operation. The object to
+     * check must already be on the stack.
+     */
+    public void instanceOf(TypeDescriptor type);
+
+    /**
+     * Generates code that increments a local integer variable by a signed 
+     * constant amount.
+     */
+    public void integerIncrement(LocalVariable local, int amount);
+
+    /**
+     * Generates code to enter the monitor on an object loaded on the stack.
+     */
+    public void monitorEnter();
+
+    /**
+     * Generates code to exit the monitor on an object loaded on the stack.
+     */
+    public void monitorExit();
+
+    /**
+     * Generates an instruction that does nothing. (No-OPeration)
+     */
+    public void nop();
+
+    /**
+     * Generates a breakpoint instruction for use in a debugging environment.
+     */
+    public void breakpoint();
+}