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The LValue.java Java example source code
/*
* Copyright (c) 1998, 2011, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* This source code is provided to illustrate the usage of a given feature
* or technique and has been deliberately simplified. Additional steps
* required for a production-quality application, such as security checks,
* input validation and proper error handling, might not be present in
* this sample code.
*/
package com.sun.tools.example.debug.expr;
import com.sun.jdi.*;
import java.util.*;
abstract class LValue {
// The JDI Value object for this LValue. Once we have this Value,
// we have to remember it since after we return the LValue object
// to the ExpressionParser, it might decide that it needs
// the 'toString' value for the LValue in which case it will
// call getMassagedValue to get this toString value. At that
// point, we don't want to call JDI a 2nd time to get the Value
// for the LValue. This is especially wrong when the LValue
// represents a member function. We would end up calling it
// a 2nd time.
//
// Unfortunately, there are several levels of calls to
// get/set values in this file. To minimize confusion,
// jdiValue is set/tested at the lowest level - right
// next to the actual calls to JDI methods to get/set the
// value in the debuggee.
protected Value jdiValue;
abstract Value getValue() throws InvocationException,
IncompatibleThreadStateException,
InvalidTypeException,
ClassNotLoadedException,
ParseException;
abstract void setValue0(Value value)
throws ParseException, InvalidTypeException,
ClassNotLoadedException;
abstract void invokeWith(List<Value> arguments) throws ParseException;
void setValue(Value value) throws ParseException {
try {
setValue0(value);
} catch (InvalidTypeException exc) {
throw new ParseException(
"Attempt to set value of incorrect type" +
exc);
} catch (ClassNotLoadedException exc) {
throw new ParseException(
"Attempt to set value before " + exc.className() + " was loaded" +
exc);
}
}
void setValue(LValue lval) throws ParseException {
setValue(lval.interiorGetValue());
}
LValue memberLValue(ExpressionParser.GetFrame frameGetter,
String fieldName) throws ParseException {
try {
return memberLValue(fieldName, frameGetter.get().thread());
} catch (IncompatibleThreadStateException exc) {
throw new ParseException("Thread not suspended");
}
}
LValue memberLValue(String fieldName, ThreadReference thread) throws ParseException {
Value val = interiorGetValue();
if ((val instanceof ArrayReference) &&
"length".equals(fieldName)){
return new LValueArrayLength((ArrayReference)val);
}
return new LValueInstanceMember(val, fieldName, thread);
}
// Return the Value for this LValue that would be used to concatenate
// to a String. IE, if it is an Object, call toString in the debuggee.
Value getMassagedValue(ExpressionParser.GetFrame frameGetter) throws ParseException {
Value vv = interiorGetValue();
// If vv is an ObjectReference, then we have to
// do the implicit call to toString().
if (vv instanceof ObjectReference &&
!(vv instanceof StringReference) &&
!(vv instanceof ArrayReference)) {
StackFrame frame;
try {
frame = frameGetter.get();
} catch (IncompatibleThreadStateException exc) {
throw new ParseException("Thread not suspended");
}
ThreadReference thread = frame.thread();
LValue toStringMember = memberLValue("toString", thread);
toStringMember.invokeWith(new ArrayList<Value>());
return toStringMember.interiorGetValue();
}
return vv;
}
Value interiorGetValue() throws ParseException {
Value value;
try {
value = getValue();
} catch (InvocationException e) {
throw new ParseException("Unable to complete expression. Exception " +
e.exception() + " thrown");
} catch (IncompatibleThreadStateException itse) {
throw new ParseException("Unable to complete expression. Thread " +
"not suspended for method invoke");
} catch (InvalidTypeException ite) {
throw new ParseException("Unable to complete expression. Method " +
"argument type mismatch");
} catch (ClassNotLoadedException tnle) {
throw new ParseException("Unable to complete expression. Method " +
"argument type " + tnle.className() +
" not yet loaded");
}
return value;
}
LValue arrayElementLValue(LValue lval) throws ParseException {
Value indexValue = lval.interiorGetValue();
int index;
if ( (indexValue instanceof IntegerValue) ||
(indexValue instanceof ShortValue) ||
(indexValue instanceof ByteValue) ||
(indexValue instanceof CharValue) ) {
index = ((PrimitiveValue)indexValue).intValue();
} else {
throw new ParseException("Array index must be a integer type");
}
return new LValueArrayElement(interiorGetValue(), index);
}
@Override
public String toString() {
try {
return interiorGetValue().toString();
} catch (ParseException e) {
return "<Parse Exception>";
}
}
static final int STATIC = 0;
static final int INSTANCE = 1;
static Field fieldByName(ReferenceType refType, String name, int kind) {
/*
* TO DO: Note that this currently fails to find superclass
* or implemented interface fields. This is due to a temporary
* limititation of RefType.fieldByName. Once that method is
* fixed, superclass fields will be found.
*/
Field field = refType.fieldByName(name);
if (field != null) {
boolean isStatic = field.isStatic();
if (((kind == STATIC) && !isStatic) ||
((kind == INSTANCE) && isStatic)) {
field = null;
}
}
/***
System.err.println("fieldByName: " + refType.name() + " " +
name + " " +
kind + " " +
(field != null));
***/
return field;
}
static List<Method> methodsByName(ReferenceType refType,
String name, int kind) {
List<Method> list = refType.methodsByName(name);
Iterator<Method> iter = list.iterator();
while (iter.hasNext()) {
Method method = iter.next();
boolean isStatic = method.isStatic();
if (((kind == STATIC) && !isStatic) ||
((kind == INSTANCE) && isStatic)) {
iter.remove();
}
}
return list;
}
static List<String> primitiveTypeNames = new ArrayList();
static {
primitiveTypeNames.add("boolean");
primitiveTypeNames.add("byte");
primitiveTypeNames.add("char");
primitiveTypeNames.add("short");
primitiveTypeNames.add("int");
primitiveTypeNames.add("long");
primitiveTypeNames.add("float");
primitiveTypeNames.add("double");
}
static final int SAME = 0;
static final int ASSIGNABLE = 1;
static final int DIFFERENT = 2;
/*
* Return SAME, DIFFERENT or ASSIGNABLE.
* SAME means each arg type is the same as type of the corr. arg.
* ASSIGNABLE means that not all the pairs are the same, but
* for those that aren't, at least the argType is assignable
* from the type of the argument value.
* DIFFERENT means that in at least one pair, the
* argType is not assignable from the type of the argument value.
* IE, one is an Apple and the other is an Orange.
*/
static int argumentsMatch(List<Type> argTypes, List arguments) {
if (argTypes.size() != arguments.size()) {
return DIFFERENT;
}
Iterator<Type> typeIter = argTypes.iterator();
Iterator<Value> valIter = arguments.iterator();
int result = SAME;
// If any pair aren't the same, change the
// result to ASSIGNABLE. If any pair aren't
// assignable, return DIFFERENT
while (typeIter.hasNext()) {
Type argType = typeIter.next();
Value value = valIter.next();
if (value == null) {
// Null values can be passed to any non-primitive argument
if (primitiveTypeNames.contains(argType.name())) {
return DIFFERENT;
}
// Else, we will assume that a null value
// exactly matches an object type.
}
if (!value.type().equals(argType)) {
if (isAssignableTo(value.type(), argType)) {
result = ASSIGNABLE;
} else {
return DIFFERENT;
}
}
}
return result;
}
// These is...AssignableTo methods are based on similar code in the JDI
// implementations of ClassType, ArrayType, and InterfaceType
static boolean isComponentAssignable(Type fromType, Type toType) {
if (fromType instanceof PrimitiveType) {
// Assignment of primitive arrays requires identical
// component types.
return fromType.equals(toType);
}
if (toType instanceof PrimitiveType) {
return false;
}
// Assignment of object arrays requires availability
// of widening conversion of component types
return isAssignableTo(fromType, toType);
}
static boolean isArrayAssignableTo(ArrayType fromType, Type toType) {
if (toType instanceof ArrayType) {
try {
Type toComponentType = ((ArrayType)toType).componentType();
return isComponentAssignable(fromType.componentType(), toComponentType);
} catch (ClassNotLoadedException e) {
// One or both component types has not yet been
// loaded => can't assign
return false;
}
}
if (toType instanceof InterfaceType) {
// Only valid InterfaceType assignee is Cloneable
return toType.name().equals("java.lang.Cloneable");
}
// Only valid ClassType assignee is Object
return toType.name().equals("java.lang.Object");
}
static boolean isAssignableTo(Type fromType, Type toType) {
if (fromType.equals(toType)) {
return true;
}
// If one is boolean, so must be the other.
if (fromType instanceof BooleanType) {
if (toType instanceof BooleanType) {
return true;
}
return false;
}
if (toType instanceof BooleanType) {
return false;
}
// Other primitive types are intermixable only with each other.
if (fromType instanceof PrimitiveType) {
if (toType instanceof PrimitiveType) {
return true;
}
return false;
}
if (toType instanceof PrimitiveType) {
return false;
}
// neither one is primitive.
if (fromType instanceof ArrayType) {
return isArrayAssignableTo((ArrayType)fromType, toType);
}
List<InterfaceType> interfaces;
if (fromType instanceof ClassType) {
ClassType superclazz = ((ClassType)fromType).superclass();
if ((superclazz != null) && isAssignableTo(superclazz, toType)) {
return true;
}
interfaces = ((ClassType)fromType).interfaces();
} else {
// fromType must be an InterfaceType
interfaces = ((InterfaceType)fromType).superinterfaces();
}
for (InterfaceType interfaze : interfaces) {
if (isAssignableTo(interfaze, toType)) {
return true;
}
}
return false;
}
static Method resolveOverload(List<Method> overloads,
List<Value> arguments)
throws ParseException {
// If there is only one method to call, we'll just choose
// that without looking at the args. If they aren't right
// the invoke will return a better error message than we
// could generate here.
if (overloads.size() == 1) {
return overloads.get(0);
}
// Resolving overloads is beyond the scope of this exercise.
// So, we will look for a method that matches exactly the
// types of the arguments. If we can't find one, then
// if there is exactly one method whose param types are assignable
// from the arg types, we will use that. Otherwise,
// it is an error. We won't guess which of multiple possible
// methods to call. And, since casts aren't implemented,
// the user can't use them to pick a particular overload to call.
// IE, the user is out of luck in this case.
Method retVal = null;
int assignableCount = 0;
for (Method mm : overloads) {
List<Type> argTypes;
try {
argTypes = mm.argumentTypes();
} catch (ClassNotLoadedException ee) {
// This probably won't happen for the
// method that we are really supposed to
// call.
continue;
}
int compare = argumentsMatch(argTypes, arguments);
if (compare == SAME) {
return mm;
}
if (compare == DIFFERENT) {
continue;
}
// Else, it is assignable. Remember it.
retVal = mm;
assignableCount++;
}
// At this point, we didn't find an exact match,
// but we found one for which the args are assignable.
//
if (retVal != null) {
if (assignableCount == 1) {
return retVal;
}
throw new ParseException("Arguments match multiple methods");
}
throw new ParseException("Arguments match no method");
}
private static class LValueLocal extends LValue {
final StackFrame frame;
final LocalVariable var;
LValueLocal(StackFrame frame, LocalVariable var) {
this.frame = frame;
this.var = var;
}
@Override
Value getValue() {
if (jdiValue == null) {
jdiValue = frame.getValue(var);
}
return jdiValue;
}
@Override
void setValue0(Value val) throws InvalidTypeException,
ClassNotLoadedException {
frame.setValue(var, val);
jdiValue = val;
}
@Override
void invokeWith(List<Value> arguments) throws ParseException {
throw new ParseException(var.name() + " is not a method");
}
}
private static class LValueInstanceMember extends LValue {
final ObjectReference obj;
final ThreadReference thread;
final Field matchingField;
final List<Method> overloads;
Method matchingMethod = null;
List<Value> methodArguments = null;
LValueInstanceMember(Value value,
String memberName,
ThreadReference thread) throws ParseException {
if (!(value instanceof ObjectReference)) {
throw new ParseException(
"Cannot access field of primitive type: " + value);
}
this.obj = (ObjectReference)value;
this.thread = thread;
ReferenceType refType = obj.referenceType();
/*
* Can't tell yet whether this LValue will be accessed as a
* field or method, so we keep track of all the possibilities
*/
matchingField = LValue.fieldByName(refType, memberName,
LValue.INSTANCE);
overloads = LValue.methodsByName(refType, memberName,
LValue.INSTANCE);
if ((matchingField == null) && overloads.size() == 0) {
throw new ParseException("No instance field or method with the name "
+ memberName + " in " + refType.name());
}
}
@Override
Value getValue() throws InvocationException, InvalidTypeException,
ClassNotLoadedException, IncompatibleThreadStateException,
ParseException {
if (jdiValue != null) {
return jdiValue;
}
if (matchingMethod == null) {
if (matchingField == null) {
throw new ParseException("No such field in " + obj.referenceType().name());
}
return jdiValue = obj.getValue(matchingField);
} else {
return jdiValue = obj.invokeMethod(thread, matchingMethod, methodArguments, 0);
}
}
@Override
void setValue0(Value val) throws ParseException,
InvalidTypeException,
ClassNotLoadedException {
if (matchingMethod != null) {
throw new ParseException("Cannot assign to a method invocation");
}
obj.setValue(matchingField, val);
jdiValue = val;
}
@Override
void invokeWith(List<Value> arguments) throws ParseException {
if (matchingMethod != null) {
throw new ParseException("Invalid consecutive invocations");
}
methodArguments = arguments;
matchingMethod = LValue.resolveOverload(overloads, arguments);
}
}
private static class LValueStaticMember extends LValue {
final ReferenceType refType;
final ThreadReference thread;
final Field matchingField;
final List<Method> overloads;
Method matchingMethod = null;
List<Value> methodArguments = null;
LValueStaticMember(ReferenceType refType,
String memberName,
ThreadReference thread) throws ParseException {
this.refType = refType;
this.thread = thread;
/*
* Can't tell yet whether this LValue will be accessed as a
* field or method, so we keep track of all the possibilities
*/
matchingField = LValue.fieldByName(refType, memberName,
LValue.STATIC);
overloads = LValue.methodsByName(refType, memberName,
LValue.STATIC);
if ((matchingField == null) && overloads.size() == 0) {
throw new ParseException("No static field or method with the name "
+ memberName + " in " + refType.name());
}
}
@Override
Value getValue() throws InvocationException, InvalidTypeException,
ClassNotLoadedException, IncompatibleThreadStateException,
ParseException {
if (jdiValue != null) {
return jdiValue;
}
if (matchingMethod == null) {
return jdiValue = refType.getValue(matchingField);
} else if (refType instanceof ClassType) {
ClassType clazz = (ClassType)refType;
return jdiValue = clazz.invokeMethod(thread, matchingMethod, methodArguments, 0);
} else {
throw new InvalidTypeException("Cannot invoke static method on " +
refType.name());
}
}
@Override
void setValue0(Value val)
throws ParseException, InvalidTypeException,
ClassNotLoadedException {
if (matchingMethod != null) {
throw new ParseException("Cannot assign to a method invocation");
}
if (!(refType instanceof ClassType)) {
throw new ParseException(
"Cannot set interface field: " + refType);
}
((ClassType)refType).setValue(matchingField, val);
jdiValue = val;
}
@Override
void invokeWith(List<Value> arguments) throws ParseException {
if (matchingMethod != null) {
throw new ParseException("Invalid consecutive invocations");
}
methodArguments = arguments;
matchingMethod = LValue.resolveOverload(overloads, arguments);
}
}
private static class LValueArrayLength extends LValue {
/*
* Since one can code "int myLen = myArray.length;",
* one might expect that these JDI calls would get a Value
* object for the length of an array in the debugee:
* Field xxx = ArrayType.fieldByName("length")
* Value lenVal= ArrayReference.getValue(xxx)
*
* However, this doesn't work because the array length isn't
* really stored as a field, and can't be accessed as such
* via JDI. Instead, the arrayRef.length() method has to be
* used.
*/
final ArrayReference arrayRef;
LValueArrayLength (ArrayReference value) {
this.arrayRef = value;
}
@Override
Value getValue() {
if (jdiValue == null) {
jdiValue = arrayRef.virtualMachine().mirrorOf(arrayRef.length());
}
return jdiValue;
}
@Override
void setValue0(Value value) throws ParseException {
throw new ParseException("Cannot set constant: " + value);
}
@Override
void invokeWith(List<Value> arguments) throws ParseException {
throw new ParseException("Array element is not a method");
}
}
private static class LValueArrayElement extends LValue {
final ArrayReference array;
final int index;
LValueArrayElement(Value value, int index) throws ParseException {
if (!(value instanceof ArrayReference)) {
throw new ParseException(
"Must be array type: " + value);
}
this.array = (ArrayReference)value;
this.index = index;
}
@Override
Value getValue() {
if (jdiValue == null) {
jdiValue = array.getValue(index);
}
return jdiValue;
}
@Override
void setValue0(Value val) throws InvalidTypeException,
ClassNotLoadedException {
array.setValue(index, val);
jdiValue = val;
}
@Override
void invokeWith(List<Value> arguments) throws ParseException {
throw new ParseException("Array element is not a method");
}
}
private static class LValueConstant extends LValue {
final Value value;
LValueConstant(Value value) {
this.value = value;
}
@Override
Value getValue() {
if (jdiValue == null) {
jdiValue = value;
}
return jdiValue;
}
@Override
void setValue0(Value val) throws ParseException {
throw new ParseException("Cannot set constant: " + value);
}
@Override
void invokeWith(List<Value> arguments) throws ParseException {
throw new ParseException("Constant is not a method");
}
}
static LValue make(VirtualMachine vm, boolean val) {
return new LValueConstant(vm.mirrorOf(val));
}
static LValue make(VirtualMachine vm, byte val) {
return new LValueConstant(vm.mirrorOf(val));
}
static LValue make(VirtualMachine vm, char val) {
return new LValueConstant(vm.mirrorOf(val));
}
static LValue make(VirtualMachine vm, short val) {
return new LValueConstant(vm.mirrorOf(val));
}
static LValue make(VirtualMachine vm, int val) {
return new LValueConstant(vm.mirrorOf(val));
}
static LValue make(VirtualMachine vm, long val) {
return new LValueConstant(vm.mirrorOf(val));
}
static LValue make(VirtualMachine vm, float val) {
return new LValueConstant(vm.mirrorOf(val));
}
static LValue make(VirtualMachine vm, double val) {
return new LValueConstant(vm.mirrorOf(val));
}
static LValue make(VirtualMachine vm, String val) throws ParseException {
return new LValueConstant(vm.mirrorOf(val));
}
static LValue makeBoolean(VirtualMachine vm, Token token) {
return make(vm, token.image.charAt(0) == 't');
}
static LValue makeCharacter(VirtualMachine vm, Token token) {
return make(vm, token.image.charAt(1));
}
static LValue makeFloat(VirtualMachine vm, Token token) {
return make(vm, Float.valueOf(token.image).floatValue());
}
static LValue makeDouble(VirtualMachine vm, Token token) {
return make(vm, Double.valueOf(token.image).doubleValue());
}
static LValue makeInteger(VirtualMachine vm, Token token) {
return make(vm, Integer.parseInt(token.image));
}
static LValue makeShort(VirtualMachine vm, Token token) {
return make(vm, Short.parseShort(token.image));
}
static LValue makeLong(VirtualMachine vm, Token token) {
return make(vm, Long.parseLong(token.image));
}
static LValue makeByte(VirtualMachine vm, Token token) {
return make(vm, Byte.parseByte(token.image));
}
static LValue makeString(VirtualMachine vm,
Token token) throws ParseException {
int len = token.image.length();
return make(vm, token.image.substring(1,len-1));
}
static LValue makeNull(VirtualMachine vm,
Token token) throws ParseException {
return new LValueConstant(null);
}
static LValue makeThisObject(VirtualMachine vm,
ExpressionParser.GetFrame frameGetter,
Token token) throws ParseException {
if (frameGetter == null) {
throw new ParseException("No current thread");
} else {
try {
StackFrame frame = frameGetter.get();
ObjectReference thisObject = frame.thisObject();
if (thisObject==null) {
throw new ParseException(
"No 'this'. In native or static method");
} else {
return new LValueConstant(thisObject);
}
} catch (IncompatibleThreadStateException exc) {
throw new ParseException("Thread not suspended");
}
}
}
static LValue makeNewObject(VirtualMachine vm,
ExpressionParser.GetFrame frameGetter,
String className, List<Value> arguments) throws ParseException {
List<ReferenceType> classes = vm.classesByName(className);
if (classes.size() == 0) {
throw new ParseException("No class named: " + className);
}
if (classes.size() > 1) {
throw new ParseException("More than one class named: " +
className);
}
ReferenceType refType = classes.get(0);
if (!(refType instanceof ClassType)) {
throw new ParseException("Cannot create instance of interface " +
className);
}
ClassType classType = (ClassType)refType;
List<Method> methods = new ArrayList(classType.methods()); // writable
Iterator<Method> iter = methods.iterator();
while (iter.hasNext()) {
Method method = iter.next();
if (!method.isConstructor()) {
iter.remove();
}
}
Method constructor = LValue.resolveOverload(methods, arguments);
ObjectReference newObject;
try {
ThreadReference thread = frameGetter.get().thread();
newObject = classType.newInstance(thread, constructor, arguments, 0);
} catch (InvocationException ie) {
throw new ParseException("Exception in " + className + " constructor: " +
ie.exception().referenceType().name());
} catch (IncompatibleThreadStateException exc) {
throw new ParseException("Thread not suspended");
} catch (Exception e) {
/*
* TO DO: Better error handling
*/
throw new ParseException("Unable to create " + className + " instance");
}
return new LValueConstant(newObject);
}
private static LValue nFields(LValue lval,
StringTokenizer izer,
ThreadReference thread)
throws ParseException {
if (!izer.hasMoreTokens()) {
return lval;
} else {
return nFields(lval.memberLValue(izer.nextToken(), thread), izer, thread);
}
}
static LValue makeName(VirtualMachine vm,
ExpressionParser.GetFrame frameGetter,
String name) throws ParseException {
StringTokenizer izer = new StringTokenizer(name, ".");
String first = izer.nextToken();
// check local variables
if (frameGetter != null) {
try {
StackFrame frame = frameGetter.get();
ThreadReference thread = frame.thread();
LocalVariable var;
try {
var = frame.visibleVariableByName(first);
} catch (AbsentInformationException e) {
var = null;
}
if (var != null) {
return nFields(new LValueLocal(frame, var), izer, thread);
} else {
ObjectReference thisObject = frame.thisObject();
if (thisObject != null) {
// check if it is a field of 'this'
LValue thisLValue = new LValueConstant(thisObject);
LValue fv;
try {
fv = thisLValue.memberLValue(first, thread);
} catch (ParseException exc) {
fv = null;
}
if (fv != null) {
return nFields(fv, izer, thread);
}
}
}
// check for class name
while (izer.hasMoreTokens()) {
List<ReferenceType> classes = vm.classesByName(first);
if (classes.size() > 0) {
if (classes.size() > 1) {
throw new ParseException("More than one class named: " +
first);
} else {
ReferenceType refType = classes.get(0);
LValue lval = new LValueStaticMember(refType,
izer.nextToken(), thread);
return nFields(lval, izer, thread);
}
}
first = first + '.' + izer.nextToken();
}
} catch (IncompatibleThreadStateException exc) {
throw new ParseException("Thread not suspended");
}
}
throw new ParseException("Name unknown: " + name);
}
static String stringValue(LValue lval, ExpressionParser.GetFrame frameGetter
) throws ParseException {
Value val = lval.getMassagedValue(frameGetter);
if (val == null) {
return "null";
}
if (val instanceof StringReference) {
return ((StringReference)val).value();
}
return val.toString(); // is this correct in all cases?
}
static LValue booleanOperation(VirtualMachine vm, Token token,
LValue rightL,
LValue leftL) throws ParseException {
String op = token.image;
Value right = rightL.interiorGetValue();
Value left = leftL.interiorGetValue();
if ( !(right instanceof PrimitiveValue) ||
!(left instanceof PrimitiveValue) ) {
if (op.equals("==")) {
return make(vm, right.equals(left));
} else if (op.equals("!=")) {
return make(vm, !right.equals(left));
} else {
throw new ParseException("Operands or '" + op +
"' must be primitive");
}
}
// can compare any numeric doubles
double rr = ((PrimitiveValue)right).doubleValue();
double ll = ((PrimitiveValue)left).doubleValue();
boolean res;
if (op.equals("<")) {
res = rr < ll;
} else if (op.equals(">")) {
res = rr > ll;
} else if (op.equals("<=")) {
res = rr <= ll;
} else if (op.equals(">=")) {
res = rr >= ll;
} else if (op.equals("==")) {
res = rr == ll;
} else if (op.equals("!=")) {
res = rr != ll;
} else {
throw new ParseException("Unknown operation: " + op);
}
return make(vm, res);
}
static LValue operation(VirtualMachine vm, Token token,
LValue rightL, LValue leftL,
ExpressionParser.GetFrame frameGetter
) throws ParseException {
String op = token.image;
Value right = rightL.interiorGetValue();
Value left = leftL.interiorGetValue();
if ((right instanceof StringReference) ||
(left instanceof StringReference)) {
if (op.equals("+")) {
// If one is an ObjectRef, we will need to invoke
// toString on it, so we need the thread.
return make(vm, stringValue(rightL, frameGetter) +
stringValue(leftL, frameGetter));
}
}
if ((right instanceof ObjectReference) ||
(left instanceof ObjectReference)) {
if (op.equals("==")) {
return make(vm, right.equals(left));
} else if (op.equals("!=")) {
return make(vm, !right.equals(left));
} else {
throw new ParseException("Invalid operation '" +
op + "' on an Object");
}
}
if ((right instanceof BooleanValue) ||
(left instanceof BooleanValue)) {
throw new ParseException("Invalid operation '" +
op + "' on a Boolean");
}
// from here on, we know it is a integer kind of type
PrimitiveValue primRight = (PrimitiveValue)right;
PrimitiveValue primLeft = (PrimitiveValue)left;
if ((primRight instanceof DoubleValue) ||
(primLeft instanceof DoubleValue)) {
double rr = primRight.doubleValue();
double ll = primLeft.doubleValue();
double res;
if (op.equals("+")) {
res = rr + ll;
} else if (op.equals("-")) {
res = rr - ll;
} else if (op.equals("*")) {
res = rr * ll;
} else if (op.equals("/")) {
res = rr / ll;
} else {
throw new ParseException("Unknown operation: " + op);
}
return make(vm, res);
}
if ((primRight instanceof FloatValue) ||
(primLeft instanceof FloatValue)) {
float rr = primRight.floatValue();
float ll = primLeft.floatValue();
float res;
if (op.equals("+")) {
res = rr + ll;
} else if (op.equals("-")) {
res = rr - ll;
} else if (op.equals("*")) {
res = rr * ll;
} else if (op.equals("/")) {
res = rr / ll;
} else {
throw new ParseException("Unknown operation: " + op);
}
return make(vm, res);
}
if ((primRight instanceof LongValue) ||
(primLeft instanceof LongValue)) {
long rr = primRight.longValue();
long ll = primLeft.longValue();
long res;
if (op.equals("+")) {
res = rr + ll;
} else if (op.equals("-")) {
res = rr - ll;
} else if (op.equals("*")) {
res = rr * ll;
} else if (op.equals("/")) {
res = rr / ll;
} else {
throw new ParseException("Unknown operation: " + op);
}
return make(vm, res);
} else {
int rr = primRight.intValue();
int ll = primLeft.intValue();
int res;
if (op.equals("+")) {
res = rr + ll;
} else if (op.equals("-")) {
res = rr - ll;
} else if (op.equals("*")) {
res = rr * ll;
} else if (op.equals("/")) {
res = rr / ll;
} else {
throw new ParseException("Unknown operation: " + op);
}
return make(vm, res);
}
}
}
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