// Copyright 2011 Palantir Technologies
//
// 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 com.palantir.ptoss.cinch.swing;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Collection;
import java.util.List;
import javax.swing.JButton;
import javax.swing.JTextField;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import org.apache.log4j.Logger;
import com.google.common.collect.ImmutableList;
import com.palantir.ptoss.cinch.core.Binding;
import com.palantir.ptoss.cinch.core.BindingContext;
import com.palantir.ptoss.cinch.core.BindingException;
import com.palantir.ptoss.cinch.core.BindingWiring;
import com.palantir.ptoss.cinch.core.ObjectFieldMethod;
/**
* A component binding that will call a method when an action occurs. This can be applied to
* any object that has an "addChangeListener" method that takes an {@link ChangeListener}.
* Normally used for any sort of {@link JButton} or for a {@link JTextField}.
*/
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.FIELD})
public @interface OnChange {
/**
* The name of the method to call when the action occurs. Must be accessible in the
* {@link BindingContext}.
*/
String call();
/**
* A boolean indicating whether or not we want to call this when the values
* is adjusting
*/
boolean onAdjust() default false;
/**
* Inner utility class that performs the runtime wiring of all {@link OnChange} bindings.
*/
static class Wiring implements BindingWiring {
private static final Logger logger = Logger.getLogger(OnChange.class);
public Collection<Binding> wire(BindingContext context) {
List<Field> actions = context.getAnnotatedFields(OnChange.class);
for (Field field : actions) {
OnChange change = field.getAnnotation(OnChange.class);
try {
wire(change, field, context);
} catch (Exception e) {
throw new BindingException("could not wire up @OnChange on " + field.getName(), e);
}
}
return ImmutableList.of();
}
private static void wire(final OnChange change, Field field, BindingContext context)
throws SecurityException, NoSuchMethodException, IllegalArgumentException, IllegalAccessException, InvocationTargetException {
String call = change.call();
if (call == null) {
throw new BindingException("call on @OnChange on " + field.getName() + " must be specified");
}
Method _adjustMethod = null;
try {
_adjustMethod = field.getType().getMethod("getValueIsAdjusting");
} catch(NoSuchMethodException nsme) {
// not a problem, leave value as null;
}
final Method adjustMethod = _adjustMethod;
final Method addChangeMethod = field.getType().getMethod("addChangeListener", ChangeListener.class);
if (addChangeMethod != null) {
final Object changeObject = context.getFieldObject(field, Object.class);
final ObjectFieldMethod ofm = context.getBindableMethod(call);
if (ofm == null) {
throw new BindingException("could not find bindable method: " + call);
}
final ChangeListener changeListener = new ChangeListener() {
public void stateChanged(ChangeEvent e) {
try {
if (adjustMethod != null && !change.onAdjust()) {
if ((Boolean) adjustMethod.invoke(changeObject)) return;
}
ofm.getMethod().invoke(ofm.getObject());
} catch (InvocationTargetException itex) {
logger.error("exception during action firing", itex.getCause());
} catch (Exception ex) {
logger.error("exception during action firing", ex);
}
}
};
addChangeMethod.invoke(changeObject, changeListener);
}
}
}
}