/*
* Copyright 2002-2014 the original author or authors.
*
* 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 org.springframework.expression.spel.ast;
import java.lang.reflect.Array;
import org.springframework.asm.MethodVisitor;
import org.springframework.asm.Type;
import org.springframework.expression.EvaluationException;
import org.springframework.expression.TypedValue;
import org.springframework.expression.spel.CodeFlow;
import org.springframework.expression.spel.ExpressionState;
/**
* Represents a reference to a type, for example "T(String)" or "T(com.somewhere.Foo)"
*
* @author Andy Clement
*/
public class TypeReference extends SpelNodeImpl {
private final int dimensions;
private transient Class<?> type;
public TypeReference(int pos, SpelNodeImpl qualifiedId) {
this(pos,qualifiedId,0);
}
public TypeReference(int pos, SpelNodeImpl qualifiedId, int dims) {
super(pos,qualifiedId);
this.dimensions = dims;
}
@Override
public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
// TODO possible optimization here if we cache the discovered type reference, but can we do that?
String typeName = (String) this.children[0].getValueInternal(state).getValue();
if (!typeName.contains(".") && Character.isLowerCase(typeName.charAt(0))) {
TypeCode tc = TypeCode.valueOf(typeName.toUpperCase());
if (tc != TypeCode.OBJECT) {
// It is a primitive type
Class<?> clazz = makeArrayIfNecessary(tc.getType());
this.exitTypeDescriptor = "Ljava/lang/Class";
this.type = clazz;
return new TypedValue(clazz);
}
}
Class<?> clazz = state.findType(typeName);
clazz = makeArrayIfNecessary(clazz);
this.exitTypeDescriptor = "Ljava/lang/Class";
this.type = clazz;
return new TypedValue(clazz);
}
private Class<?> makeArrayIfNecessary(Class<?> clazz) {
if (this.dimensions != 0) {
for (int i = 0; i < this.dimensions; i++) {
Object array = Array.newInstance(clazz, 0);
clazz = array.getClass();
}
}
return clazz;
}
@Override
public String toStringAST() {
StringBuilder sb = new StringBuilder("T(");
sb.append(getChild(0).toStringAST());
for (int d = 0; d < this.dimensions; d++) {
sb.append("[]");
}
sb.append(")");
return sb.toString();
}
@Override
public boolean isCompilable() {
return (this.exitTypeDescriptor != null);
}
@Override
public void generateCode(MethodVisitor mv, CodeFlow cf) {
// TODO Future optimization - if followed by a static method call, skip generating code here
if (this.type.isPrimitive()) {
if (this.type == Integer.TYPE) {
mv.visitFieldInsn(GETSTATIC, "java/lang/Integer", "TYPE", "Ljava/lang/Class;");
}
else if (this.type == Boolean.TYPE) {
mv.visitFieldInsn(GETSTATIC, "java/lang/Boolean", "TYPE", "Ljava/lang/Class;");
}
else if (this.type == Byte.TYPE) {
mv.visitFieldInsn(GETSTATIC, "java/lang/Byte", "TYPE", "Ljava/lang/Class;");
}
else if (this.type == Short.TYPE) {
mv.visitFieldInsn(GETSTATIC, "java/lang/Short", "TYPE", "Ljava/lang/Class;");
}
else if (this.type == Double.TYPE) {
mv.visitFieldInsn(GETSTATIC, "java/lang/Double", "TYPE", "Ljava/lang/Class;");
}
else if (this.type == Character.TYPE) {
mv.visitFieldInsn(GETSTATIC, "java/lang/Character", "TYPE", "Ljava/lang/Class;");
}
else if (this.type == Float.TYPE) {
mv.visitFieldInsn(GETSTATIC, "java/lang/Float", "TYPE", "Ljava/lang/Class;");
}
else if (this.type == Long.TYPE) {
mv.visitFieldInsn(GETSTATIC, "java/lang/Long", "TYPE", "Ljava/lang/Class;");
}
else if (this.type == Boolean.TYPE) {
mv.visitFieldInsn(GETSTATIC, "java/lang/Boolean", "TYPE", "Ljava/lang/Class;");
}
}
else {
mv.visitLdcInsn(Type.getType(this.type));
}
cf.pushDescriptor(this.exitTypeDescriptor);
}
}