groovy.beans.BindableASTTransformation Maven / Gradle / Ivy
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/*
* 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 groovy.beans;
import org.codehaus.groovy.ast.ASTNode;
import org.codehaus.groovy.ast.AnnotatedNode;
import org.codehaus.groovy.ast.AnnotationNode;
import org.codehaus.groovy.ast.ClassHelper;
import org.codehaus.groovy.ast.ClassNode;
import org.codehaus.groovy.ast.FieldNode;
import org.codehaus.groovy.ast.MethodNode;
import org.codehaus.groovy.ast.Parameter;
import org.codehaus.groovy.ast.PropertyNode;
import org.codehaus.groovy.ast.expr.Expression;
import org.codehaus.groovy.ast.stmt.BlockStatement;
import org.codehaus.groovy.ast.stmt.Statement;
import org.codehaus.groovy.ast.tools.PropertyNodeUtils;
import org.codehaus.groovy.control.CompilePhase;
import org.codehaus.groovy.control.SourceUnit;
import org.codehaus.groovy.control.messages.SimpleMessage;
import org.codehaus.groovy.transform.ASTTransformation;
import org.codehaus.groovy.transform.GroovyASTTransformation;
import org.objectweb.asm.Opcodes;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import static org.apache.groovy.ast.tools.ClassNodeUtils.addGeneratedMethod;
import static org.codehaus.groovy.ast.tools.GeneralUtils.args;
import static org.codehaus.groovy.ast.tools.GeneralUtils.assignX;
import static org.codehaus.groovy.ast.tools.GeneralUtils.callThisX;
import static org.codehaus.groovy.ast.tools.GeneralUtils.callX;
import static org.codehaus.groovy.ast.tools.GeneralUtils.constX;
import static org.codehaus.groovy.ast.tools.GeneralUtils.ctorX;
import static org.codehaus.groovy.ast.tools.GeneralUtils.declS;
import static org.codehaus.groovy.ast.tools.GeneralUtils.fieldX;
import static org.codehaus.groovy.ast.tools.GeneralUtils.localVarX;
import static org.codehaus.groovy.ast.tools.GeneralUtils.param;
import static org.codehaus.groovy.ast.tools.GeneralUtils.params;
import static org.codehaus.groovy.ast.tools.GeneralUtils.returnS;
import static org.codehaus.groovy.ast.tools.GeneralUtils.stmt;
import static org.codehaus.groovy.ast.tools.GeneralUtils.varX;
/**
* Handles generation of code for the {@code @Bindable} annotation when {@code @Vetoable}
* is not present.
*
* Generally, it adds (if needed) a PropertyChangeSupport field and
* the needed add/removePropertyChangeListener methods to support the
* listeners.
*
* It also generates the setter and wires the setter through the
* PropertyChangeSupport.
*
* If a {@link Vetoable} annotation is detected it does nothing and
* lets the {@link VetoableASTTransformation} handle all the changes.
*/
@GroovyASTTransformation(phase = CompilePhase.CANONICALIZATION)
public class BindableASTTransformation implements ASTTransformation, Opcodes {
protected static final ClassNode boundClassNode = ClassHelper.make(Bindable.class);
/**
* Convenience method to see if an annotated node is {@code @Bindable}.
*
* @param node the node to check
* @return true if the node is bindable
*/
public static boolean hasBindableAnnotation(AnnotatedNode node) {
for (AnnotationNode annotation : node.getAnnotations()) {
if (boundClassNode.equals(annotation.getClassNode())) {
return true;
}
}
return false;
}
/**
* Handles the bulk of the processing, mostly delegating to other methods.
*
* @param nodes the ast nodes
* @param source the source unit for the nodes
*/
@Override
public void visit(ASTNode[] nodes, SourceUnit source) {
if (!(nodes[0] instanceof AnnotationNode) || !(nodes[1] instanceof AnnotatedNode)) {
throw new RuntimeException("Internal error: wrong types: $node.class / $parent.class");
}
AnnotationNode node = (AnnotationNode) nodes[0];
AnnotatedNode parent = (AnnotatedNode) nodes[1];
if (VetoableASTTransformation.hasVetoableAnnotation(parent)) {
// VetoableASTTransformation will handle both @Bindable and @Vetoable
return;
}
ClassNode declaringClass = parent.getDeclaringClass();
if (parent instanceof FieldNode) {
if ((((FieldNode) parent).getModifiers() & Opcodes.ACC_FINAL) != 0) {
source.getErrorCollector().addErrorAndContinue("@groovy.beans.Bindable cannot annotate a final property.", node, source);
}
if (VetoableASTTransformation.hasVetoableAnnotation(parent.getDeclaringClass())) {
// VetoableASTTransformation will handle both @Bindable and @Vetoable
return;
}
addListenerToProperty(source, node, declaringClass, (FieldNode) parent);
} else if (parent instanceof ClassNode) {
addListenerToClass(source, (ClassNode) parent);
}
}
private void addListenerToProperty(SourceUnit source, AnnotationNode node, ClassNode declaringClass, FieldNode field) {
String fieldName = field.getName();
for (PropertyNode propertyNode : declaringClass.getProperties()) {
if (propertyNode.getName().equals(fieldName)) {
if (field.isStatic()) {
//noinspection ThrowableInstanceNeverThrown
source.getErrorCollector().addErrorAndContinue("@groovy.beans.Bindable cannot annotate a static property.", node, source);
} else {
if (needsPropertyChangeSupport(declaringClass, source)) {
addPropertyChangeSupport(declaringClass);
}
createListenerSetter(declaringClass, propertyNode);
}
return;
}
}
//noinspection ThrowableInstanceNeverThrown
source.getErrorCollector().addErrorAndContinue("@groovy.beans.Bindable must be on a property, not a field. Try removing the private, protected, or public modifier.", node, source);
}
private void addListenerToClass(SourceUnit source, ClassNode classNode) {
if (needsPropertyChangeSupport(classNode, source)) {
addPropertyChangeSupport(classNode);
}
for (PropertyNode propertyNode : classNode.getProperties()) {
FieldNode field = propertyNode.getField();
// look to see if per-field handlers will catch this one...
if (hasBindableAnnotation(field)
|| ((field.getModifiers() & Opcodes.ACC_FINAL) != 0)
|| field.isStatic()
|| VetoableASTTransformation.hasVetoableAnnotation(field))
{
// explicitly labeled properties are already handled,
// don't transform final properties
// don't transform static properties
// VetoableASTTransformation will handle both @Bindable and @Vetoable
continue;
}
createListenerSetter(classNode, propertyNode);
}
}
/*
* Wrap an existing setter.
*/
private static void wrapSetterMethod(ClassNode classNode, PropertyNode propertyNode) {
String getterName = propertyNode.getGetterNameOrDefault();
MethodNode setter = classNode.getSetterMethod(propertyNode.getSetterNameOrDefault());
if (setter != null) {
// Get the existing code block
Statement code = setter.getCode();
Expression oldValue = localVarX("$oldValue");
Expression newValue = localVarX("$newValue");
BlockStatement block = new BlockStatement();
// create a local variable to hold the old value from the getter
block.addStatement(declS(oldValue, callThisX(getterName)));
// call the existing block, which will presumably set the value properly
block.addStatement(code);
// get the new value to emit in the event
block.addStatement(declS(newValue, callThisX(getterName)));
// add the firePropertyChange method call
block.addStatement(stmt(callThisX("firePropertyChange", args(constX(propertyNode.getName()), oldValue, newValue))));
// replace the existing code block with our new one
setter.setCode(block);
}
}
private void createListenerSetter(ClassNode classNode, PropertyNode propertyNode) {
String setterName = propertyNode.getSetterNameOrDefault();
if (classNode.getMethods(setterName).isEmpty()) {
Statement setterBlock = createBindableStatement(propertyNode, fieldX(propertyNode.getField()));
// create method void ( fieldName)
createSetterMethod(classNode, propertyNode, setterName, setterBlock);
} else {
wrapSetterMethod(classNode, propertyNode);
}
}
/**
* Creates a statement body similar to:
* this.firePropertyChange("field", field, field = value)
*
* @param propertyNode the field node for the property
* @param fieldExpression a field expression for setting the property value
* @return the created statement
*/
protected Statement createBindableStatement(PropertyNode propertyNode, Expression fieldExpression) {
// create statementBody
return stmt(callThisX("firePropertyChange", args(constX(propertyNode.getName()), fieldExpression, assignX(fieldExpression, varX("value")))));
}
/**
* Creates a setter method with the given body.
*
* @param declaringClass the class to which we will add the setter
* @param propertyNode the field to back the setter
* @param setterName the name of the setter
* @param setterBlock the statement representing the setter block
*/
protected void createSetterMethod(ClassNode declaringClass, PropertyNode propertyNode, String setterName, Statement setterBlock) {
MethodNode setter = new MethodNode(
setterName,
PropertyNodeUtils.adjustPropertyModifiersForMethod(propertyNode),
ClassHelper.VOID_TYPE,
params(param(propertyNode.getType(), "value")),
ClassNode.EMPTY_ARRAY,
setterBlock);
setter.setSynthetic(true);
// add it to the class
addGeneratedMethod(declaringClass, setter);
}
/**
* Snoops through the declaring class and all parents looking for methods
* void addPropertyChangeListener(PropertyChangeListener),
* void removePropertyChangeListener(PropertyChangeListener), and
* void firePropertyChange(String, Object, Object). If any are defined all
* must be defined or a compilation error results.
*
* @param declaringClass the class to search
* @param sourceUnit the source unit, for error reporting. {@code @NotNull}.
* @return true if property change support should be added
*/
protected boolean needsPropertyChangeSupport(ClassNode declaringClass, SourceUnit sourceUnit) {
boolean foundAdd = false, foundRemove = false, foundFire = false;
ClassNode consideredClass = declaringClass;
while (consideredClass!= null) {
for (MethodNode method : consideredClass.getMethods()) {
// just check length, MOP will match it up
foundAdd = foundAdd || "addPropertyChangeListener".equals(method.getName()) && method.getParameters().length == 1;
foundRemove = foundRemove || "removePropertyChangeListener".equals(method.getName()) && method.getParameters().length == 1;
foundFire = foundFire || "firePropertyChange".equals(method.getName()) && method.getParameters().length == 3;
if (foundAdd && foundRemove && foundFire) {
return false;
}
}
consideredClass = consideredClass.getSuperClass();
}
// check if a super class has @Bindable annotations
consideredClass = declaringClass.getSuperClass();
while (consideredClass!=null) {
if (hasBindableAnnotation(consideredClass)) return false;
for (FieldNode field : consideredClass.getFields()) {
if (hasBindableAnnotation(field)) return false;
}
consideredClass = consideredClass.getSuperClass();
}
if (foundAdd || foundRemove || foundFire) {
sourceUnit.getErrorCollector().addErrorAndContinue(
new SimpleMessage("@Bindable cannot be processed on "
+ declaringClass.getName()
+ " because some but not all of addPropertyChangeListener, removePropertyChange, and firePropertyChange were declared in the current or super classes.",
sourceUnit)
);
return false;
}
return true;
}
/**
* Adds the necessary field and methods to support property change support.
*
* Adds a new field:
*
* protected final java.beans.PropertyChangeSupport this$PropertyChangeSupport = new java.beans.PropertyChangeSupport(this)"
*
*
* Also adds support methods:
*
* public void addPropertyChangeListener(java.beans.PropertyChangeListener)
* public void addPropertyChangeListener(String, java.beans.PropertyChangeListener)
* public void removePropertyChangeListener(java.beans.PropertyChangeListener)
* public void removePropertyChangeListener(String, java.beans.PropertyChangeListener)
* public java.beans.PropertyChangeListener[] getPropertyChangeListeners()
*
*
* @param declaringClass the class to which we add the support field and methods
*/
protected void addPropertyChangeSupport(ClassNode declaringClass) {
ClassNode pcsClassNode = ClassHelper.make(PropertyChangeSupport.class);
ClassNode pclClassNode = ClassHelper.make(PropertyChangeListener.class);
//String pcsFieldName = "this$propertyChangeSupport";
// add field:
// protected final PropertyChangeSupport this$propertyChangeSupport = new java.beans.PropertyChangeSupport(this)
FieldNode pcsField = declaringClass.addField(
"this$propertyChangeSupport",
ACC_FINAL | ACC_PRIVATE | ACC_SYNTHETIC,
pcsClassNode,
ctorX(pcsClassNode, args(varX("this"))));
// add method:
// void addPropertyChangeListener(listener) {
// this$propertyChangeSupport.addPropertyChangeListener(listener)
// }
addGeneratedMethod(declaringClass,
new MethodNode(
"addPropertyChangeListener",
ACC_PUBLIC,
ClassHelper.VOID_TYPE,
params(param(pclClassNode, "listener")),
ClassNode.EMPTY_ARRAY,
stmt(callX(fieldX(pcsField), "addPropertyChangeListener", args(varX("listener", pclClassNode))))));
// add method:
// void addPropertyChangeListener(name, listener) {
// this$propertyChangeSupport.addPropertyChangeListener(name, listener)
// }
addGeneratedMethod(declaringClass,
new MethodNode(
"addPropertyChangeListener",
ACC_PUBLIC,
ClassHelper.VOID_TYPE,
params(param(ClassHelper.STRING_TYPE, "name"), param(pclClassNode, "listener")),
ClassNode.EMPTY_ARRAY,
stmt(callX(fieldX(pcsField), "addPropertyChangeListener", args(varX("name", ClassHelper.STRING_TYPE), varX("listener", pclClassNode))))));
// add method:
// boolean removePropertyChangeListener(listener) {
// return this$propertyChangeSupport.removePropertyChangeListener(listener);
// }
addGeneratedMethod(declaringClass,
new MethodNode(
"removePropertyChangeListener",
ACC_PUBLIC,
ClassHelper.VOID_TYPE,
params(param(pclClassNode, "listener")),
ClassNode.EMPTY_ARRAY,
stmt(callX(fieldX(pcsField), "removePropertyChangeListener", args(varX("listener", pclClassNode))))));
// add method: void removePropertyChangeListener(name, listener)
addGeneratedMethod(declaringClass,
new MethodNode(
"removePropertyChangeListener",
ACC_PUBLIC,
ClassHelper.VOID_TYPE,
params(param(ClassHelper.STRING_TYPE, "name"), param(pclClassNode, "listener")),
ClassNode.EMPTY_ARRAY,
stmt(callX(fieldX(pcsField), "removePropertyChangeListener", args(varX("name", ClassHelper.STRING_TYPE), varX("listener", pclClassNode))))));
// add method:
// void firePropertyChange(String name, Object oldValue, Object newValue) {
// this$propertyChangeSupport.firePropertyChange(name, oldValue, newValue)
// }
addGeneratedMethod(declaringClass,
new MethodNode(
"firePropertyChange",
ACC_PUBLIC,
ClassHelper.VOID_TYPE,
params(param(ClassHelper.STRING_TYPE, "name"), param(ClassHelper.OBJECT_TYPE, "oldValue"), param(ClassHelper.OBJECT_TYPE, "newValue")),
ClassNode.EMPTY_ARRAY,
stmt(callX(fieldX(pcsField), "firePropertyChange", args(varX("name", ClassHelper.STRING_TYPE), varX("oldValue"), varX("newValue"))))));
// add method:
// PropertyChangeListener[] getPropertyChangeListeners() {
// return this$propertyChangeSupport.getPropertyChangeListeners
// }
addGeneratedMethod(declaringClass,
new MethodNode(
"getPropertyChangeListeners",
ACC_PUBLIC,
pclClassNode.makeArray(),
Parameter.EMPTY_ARRAY,
ClassNode.EMPTY_ARRAY,
returnS(callX(fieldX(pcsField), "getPropertyChangeListeners"))));
// add method:
// PropertyChangeListener[] getPropertyChangeListeners(String name) {
// return this$propertyChangeSupport.getPropertyChangeListeners(name)
// }
addGeneratedMethod(declaringClass,
new MethodNode(
"getPropertyChangeListeners",
ACC_PUBLIC,
pclClassNode.makeArray(),
params(param(ClassHelper.STRING_TYPE, "name")),
ClassNode.EMPTY_ARRAY,
returnS(callX(fieldX(pcsField), "getPropertyChangeListeners", args(varX("name", ClassHelper.STRING_TYPE))))));
}
}