/*
* 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.codehaus.groovy.ast.expr;
import org.codehaus.groovy.ast.ClassHelper;
import org.codehaus.groovy.ast.ClassNode;
import org.codehaus.groovy.ast.GroovyCodeVisitor;
import org.codehaus.groovy.ast.Variable;
/**
* Represents a local variable name, the simplest form of expression. e.g. "foo".
*
* @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
*/
public class VariableExpression extends Expression implements Variable {
// The following fields are only used internally; every occurrence of a user-defined expression of the same kind
// has its own instance so as to preserve line information. Consequently, to test for such an expression, don't
// compare against the field but call isXXXExpression() instead.
public static final VariableExpression THIS_EXPRESSION = new VariableExpression("this", ClassHelper.DYNAMIC_TYPE);
public static final VariableExpression SUPER_EXPRESSION = new VariableExpression("super", ClassHelper.DYNAMIC_TYPE);
private final String variable;
private int modifiers;
private boolean inStaticContext;
private boolean isDynamicTyped=false;
private Variable accessedVariable;
boolean closureShare=false;
boolean useRef=false;
private final ClassNode originType;
public Variable getAccessedVariable() {
return accessedVariable;
}
public void setAccessedVariable(Variable origin) {
this.accessedVariable = origin;
}
public VariableExpression(String variable, ClassNode type) {
this.variable = variable;
originType = type;
setType(ClassHelper.getWrapper(type));
}
public VariableExpression(String variable) {
this(variable, ClassHelper.DYNAMIC_TYPE);
}
public VariableExpression(Variable variable) {
this(variable.getName(), variable.getOriginType());
setAccessedVariable(variable);
setModifiers(variable.getModifiers());
}
public void visit(GroovyCodeVisitor visitor) {
visitor.visitVariableExpression(this);
}
public Expression transformExpression(ExpressionTransformer transformer) {
return this;
}
public String getText() {
return variable;
}
public String getName() {
return variable;
}
public String toString() {
return super.toString() + "[variable: " + variable + (this.isDynamicTyped() ? "" : " type: " + getType()) + "]";
}
public Expression getInitialExpression() {
return null;
}
public boolean hasInitialExpression() {
return false;
}
public boolean isInStaticContext() {
if (accessedVariable!=null && accessedVariable!=this) return accessedVariable.isInStaticContext();
return inStaticContext;
}
public void setInStaticContext(boolean inStaticContext) {
this.inStaticContext = inStaticContext;
}
/**
* Set the type of this variable. If you call this method from an AST transformation and that
* the {@link #getAccessedVariable() accessed variable} is ({@link #isClosureSharedVariable() shared},
* this operation is unsafe and may lead to a verify error at compile time. Instead, set the type of
* the {@link #getAccessedVariable() accessed variable}
* @param cn the type to be set on this variable
*/
public void setType(ClassNode cn){
super.setType(cn);
isDynamicTyped |= ClassHelper.DYNAMIC_TYPE==cn;
}
public boolean isDynamicTyped() {
if (accessedVariable!=null && accessedVariable!=this) return accessedVariable.isDynamicTyped();
return isDynamicTyped;
}
/**
* Tells if this variable or the accessed variable is used in a closure context, like in the following
* example :
* <pre>def str = 'Hello'
* def cl = { println str }
* </pre>
* The "str" variable is closure shared.
* @return true if this variable is used in a closure
*/
public boolean isClosureSharedVariable() {
if (accessedVariable!=null && accessedVariable!=this) return accessedVariable.isClosureSharedVariable();
return closureShare;
}
/**
* Use this method to tell if a variable is used in a closure, like in the following example:
* <pre>def str = 'Hello'
* def cl = { println str }
* </pre>
* The "str" variable is closure shared. The variable expression inside the closure references an
* accessed variable "str" which must have the closure shared flag set.
* @param inClosure tells if this variable is later referenced in a closure
*/
public void setClosureSharedVariable(boolean inClosure) {
closureShare = inClosure;
}
public int getModifiers() {
return modifiers;
}
/**
* For internal use only. This flag is used by compiler internals and should probably
* be converted to a node metadata in future.
* @param useRef
*/
public void setUseReferenceDirectly(boolean useRef) {
this.useRef = useRef;
}
/**
* For internal use only. This flag is used by compiler internals and should probably
* be converted to a node metadata in future.
*/
public boolean isUseReferenceDirectly() {
return useRef;
}
public ClassNode getType() {
if (accessedVariable!=null && accessedVariable!=this) return accessedVariable.getType();
return super.getType();
}
/**
* Returns the type which was used when this variable expression was created. For example,
* {@link #getType()} may return a boxed type while this method would return the primitive type.
* @return the type which was used to define this variable expression
*/
public ClassNode getOriginType() {
if (accessedVariable!=null && accessedVariable!=this) return accessedVariable.getOriginType();
return originType;
}
public boolean isThisExpression() {
return "this".equals(variable);
}
public boolean isSuperExpression() {
return "super".equals(variable);
}
public void setModifiers(int modifiers) {
this.modifiers = modifiers;
}
}