org.apache.tools.ant.taskdefs.condition.HasMethod Maven / Gradle / Ivy
/*
* 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.apache.tools.ant.taskdefs.condition;
import org.apache.tools.ant.types.Path;
import org.apache.tools.ant.types.Reference;
import org.apache.tools.ant.AntClassLoader;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.ProjectComponent;
import java.lang.reflect.Method;
import java.lang.reflect.Field;
/**
* test for a method
*/
public class HasMethod extends ProjectComponent implements Condition {
private String classname;
private String method;
private String field;
private Path classpath;
private AntClassLoader loader;
private boolean ignoreSystemClasses = false;
/**
* Set the classpath to be used when searching for classes and resources.
*
* @param classpath an Ant Path object containing the search path.
*/
public void setClasspath(Path classpath) {
createClasspath().append(classpath);
}
/**
* Classpath to be used when searching for classes and resources.
*
* @return an empty Path instance to be configured by Ant.
*/
public Path createClasspath() {
if (this.classpath == null) {
this.classpath = new Path(getProject());
}
return this.classpath.createPath();
}
/**
* Set the classpath by reference.
*
* @param r a Reference to a Path instance to be used as the classpath
* value.
*/
public void setClasspathRef(Reference r) {
createClasspath().setRefid(r);
}
/**
* Set the classname attribute.
* @param classname the name of the class to check.
*/
public void setClassname(String classname) {
this.classname = classname;
}
/**
* Set the name of the method.
* @param method the name of the method to check.
*/
public void setMethod(String method) {
this.method = method;
}
/**
* Set the name of the field.
* @param field the name of the field to check.
*/
public void setField(String field) {
this.field = field;
}
/**
* Set whether to ignore system classes when looking for the class.
* @param ignoreSystemClasses a boolean value.
*/
public void setIgnoreSystemClasses(boolean ignoreSystemClasses) {
this.ignoreSystemClasses = ignoreSystemClasses;
}
/**
* Check if a given class can be loaded.
*/
private Class loadClass(String classname) {
try {
if (ignoreSystemClasses) {
loader = getProject().createClassLoader(classpath);
loader.setParentFirst(false);
loader.addJavaLibraries();
try {
return loader.findClass(classname);
} catch (SecurityException se) {
// class found but restricted name
throw new BuildException("class \"" + classname
+ "\" was found but a"
+ " SecurityException has been"
+ " raised while loading it",
se);
}
} else if (loader != null) {
// How do we ever get here?
return loader.loadClass(classname);
} else {
ClassLoader l = this.getClass().getClassLoader();
// Can return null to represent the bootstrap class loader.
// see API docs of Class.getClassLoader.
if (l != null) {
return Class.forName(classname, true, l);
} else {
return Class.forName(classname);
}
}
} catch (ClassNotFoundException e) {
throw new BuildException("class \"" + classname
+ "\" was not found");
} catch (NoClassDefFoundError e) {
throw new BuildException("Could not load dependent class \""
+ e.getMessage()
+ "\" for class \"" + classname + "\"");
}
}
/** {@inheritDoc}. */
public boolean eval() throws BuildException {
if (classname == null) {
throw new BuildException("No classname defined");
}
ClassLoader preLoadClass = loader;
try {
Class clazz = loadClass(classname);
if (method != null) {
return isMethodFound(clazz);
}
if (field != null) {
return isFieldFound(clazz);
}
throw new BuildException("Neither method nor field defined");
} finally {
if (preLoadClass != loader && loader != null) {
loader.cleanup();
loader = null;
}
}
}
private boolean isFieldFound(Class clazz) {
Field[] fields = clazz.getDeclaredFields();
for (int i = 0; i < fields.length; i++) {
Field fieldEntry = fields[i];
if (fieldEntry.getName().equals(field)) {
return true;
}
}
return false;
}
private boolean isMethodFound(Class clazz) {
Method[] methods = clazz.getDeclaredMethods();
for (int i = 0; i < methods.length; i++) {
Method methodEntry = methods[i];
if (methodEntry.getName().equals(method)) {
return true;
}
}
return false;
}
}