org.netbeans.spi.debugger.ContextAwareSupport 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 org.netbeans.spi.debugger;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.netbeans.debugger.registry.ContextAwareServiceHandler;
import org.openide.util.Exceptions;
import org.openide.util.Lookup;
/**
* Support class for context-aware debugger services.
*
* @author Martin Entlicher
* @since 1.16
*/
public final class ContextAwareSupport {
private ContextAwareSupport() {}
/**
* A helper method that creates a context-aware debugger service.
* The service must be a public class with public constructor or a public
* static method. The constructor or method takes
* no arguments or takes {@link ContextProvider} as an argument.
*
* This method is typically called by the implementation of {@link ContextAwareService}
* to create an instance with the given context.
*
* @param service The full class name or static method that ends with '()'
* @param context The context with which is the service to be created
* @return The instance of the service with the given context.
* @since 1.16
*/
public static Object createInstance(String service, ContextProvider context) {
try {
ClassLoader cl = org.openide.util.Lookup.getDefault().lookup(ClassLoader.class);
String method = null;
if (service.endsWith("()")) {
int lastdot = service.lastIndexOf('.');
if (lastdot < 0) {
Exceptions.printStackTrace(
new IllegalStateException("Bad service - dot before method name is missing: " +
"'" + service + "'."));
return null;
}
method = service.substring(lastdot + 1, service.length() - 2).trim();
service = service.substring(0, lastdot);
}
Class cls = cl.loadClass (service);
Object o = null;
if (method != null) {
Method m = null;
if (context != null) {
try {
m = cls.getDeclaredMethod(method, new Class[] { ContextProvider.class });
} catch (NoSuchMethodException nsmex) {}
}
if (m == null) {
try {
m = cls.getDeclaredMethod(method, new Class[] { });
} catch (NoSuchMethodException nsmex) {}
}
if (m != null) {
o = m.invoke(null, (m.getParameterTypes().length == 0)
? new Object[] {} : new Object[] { context });
}
}
if (o == null && context != null) {
Constructor[] cs = cls.getConstructors ();
int i, k = cs.length;
for (i = 0; i < k; i++) {
Constructor c = cs [i];
if (c.getParameterTypes ().length != 1 ||
!ContextProvider.class.isAssignableFrom(c.getParameterTypes()[0])) {
continue;
}
try {
o = c.newInstance (new Object[] {context});
} catch (IllegalAccessException e) {
Exceptions.printStackTrace(Exceptions.attachMessage(e, "service: " + service));
} catch (IllegalArgumentException e) {
Exceptions.printStackTrace(Exceptions.attachMessage(e, "service: " + service));
}
}
}
if (o == null)
o = cls.getDeclaredConstructor().newInstance();
if (Logger.getLogger(ContextAwareSupport.class.getName()).isLoggable(Level.FINE)) {
Logger.getLogger(ContextAwareSupport.class.getName()).fine("instance "+o+" created.");
}
return o;
} catch (ClassNotFoundException e) {
Exceptions.printStackTrace(
Exceptions.attachMessage(
e,
"The service "+service+" not found."));
} catch (InstantiationException | NoSuchMethodException e) {
Exceptions.printStackTrace(
Exceptions.attachMessage(
e,
"The service "+service+" can not be instantiated. Context = "+context));
} catch (IllegalAccessException e) {
Exceptions.printStackTrace(
Exceptions.attachMessage(
e,
"The service "+service+" can not be accessed. Context = "+context));
} catch (InvocationTargetException ex) {
if (ex.getCause() instanceof ThreadDeath) {
throw (ThreadDeath) ex.getCause();
}
Exceptions.printStackTrace(
Exceptions.attachMessage(
ex,
"The service "+service+" can not be created. Context = "+context));
} catch (ExceptionInInitializerError ex) {
Exceptions.printStackTrace(
Exceptions.attachMessage(
ex,
"The service "+service+" can not be initialized. Context = "+context));
}
return null;
}
/**
* Creates instance of ContextAwareService based on layer.xml
* attribute values
*
* @param attrs attributes loaded from layer.xml
* @return new ContextAwareService instance
*/
static ContextAwareService createService(Map attrs) throws ClassNotFoundException {
String serviceName = (String) attrs.get(ContextAwareServiceHandler.SERVICE_NAME);
String serviceClasses = (String) attrs.get(ContextAwareServiceHandler.SERVICE_CLASSES);
if (serviceClasses == null) {
serviceClasses = (String) attrs.get("instanceOf");
}
String[] serviceClassNames = splitClasses(serviceClasses);
//Map methodValues = new HashMap(attrs); - MUST NOT DO THAT! Creates a loop initializing the entries from XML
//methodValues.remove(SERVICE_NAME);
//methodValues.remove(SERVICE_CLASS);
ClassLoader cl = Lookup.getDefault().lookup(ClassLoader.class);
Class[] classes = new Class[serviceClassNames.length + 1];
classes[0] = ContextAwareService.class;
for (int i = 0; i < serviceClassNames.length; i++) {
classes[i+1] = Class.forName(serviceClassNames[i], true, cl);
}
return (ContextAwareService)
Proxy.newProxyInstance(
cl,
classes,
new ContextAwareServiceHandler(serviceName, classes, Collections.emptyMap()));
}
private static String[] splitClasses(String classes) {
return classes.split("[, ]+");
}
}