/*
* Copyright 2003-2004 The Apache Software Foundation
*
* 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 org.apache.tools.ant.taskdefs;
import org.apache.tools.ant.types.Path;
import org.apache.tools.ant.Task;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.Project;
import org.apache.tools.ant.AntClassLoader;
import java.net.URL;
/**
* Find a class or resource on the supplied classpath, or the
* system classpath if none is supplied. The named property is set if
* the item can be found. For example
* <pre>
* <whichresource resource="/log4j.properties"
* property="log4j.url" >
* </pre>
* @author steve loughran while stuck in Enumclaw, WA, with a broken down car
* @since Ant 1.6
* @ant.attribute.group name="oneof" description="Exactly one of these two"
*/
public class WhichResource extends Task {
/**
* our classpath
*/
private Path classpath;
/**
* class to look for
*/
private String classname;
/**
* resource to look for
*/
private String resource;
/**
* property to set
*/
private String property;
/**
* Set the classpath to be used for this compilation.
* @param cp the classpath to be used.
*/
public void setClasspath(Path cp) {
if (classpath == null) {
classpath = cp;
} else {
classpath.append(cp);
}
}
/**
* Adds a path to the classpath.
* @return a classpath to be configured.
*/
public Path createClasspath() {
if (classpath == null) {
classpath = new Path(getProject());
}
return classpath.createPath();
}
/**
* validate
*/
private void validate() {
int setcount = 0;
if (classname != null) {
setcount++;
}
if (resource != null) {
setcount++;
}
if (setcount == 0) {
throw new BuildException(
"One of classname or resource must be specified");
}
if (setcount > 1) {
throw new BuildException(
"Only one of classname or resource can be specified");
}
if (property == null) {
throw new BuildException("No property defined");
}
}
/**
* execute it
* @throws BuildException
*/
public void execute() throws BuildException {
validate();
if (classpath != null) {
getProject().log("using user supplied classpath: " + classpath,
Project.MSG_DEBUG);
classpath = classpath.concatSystemClasspath("ignore");
} else {
classpath = new Path(getProject());
classpath = classpath.concatSystemClasspath("only");
getProject().log("using system classpath: " + classpath, Project.MSG_DEBUG);
}
AntClassLoader loader;
loader = new AntClassLoader(getProject().getCoreLoader(),
getProject(),
classpath, false);
String location = null;
if (classname != null) {
//convert a class name into a resource
resource = classname.replace('.', '/') + ".class";
}
if (resource == null) {
throw new BuildException("One of class or resource is required");
}
if (resource.startsWith("/")) {
resource = resource.substring(1);
}
log("Searching for " + resource, Project.MSG_VERBOSE);
URL url;
url = loader.getResource(resource);
if (url != null) {
//set the property
location = url.toExternalForm();
getProject().setNewProperty(property, location);
}
}
/**
* name the resource to look for
* @param resource the name of the resource to look for.
* @ant.attribute group="oneof"
*/
public void setResource(String resource) {
this.resource = resource;
}
/**
* name the class to look for
* @param classname the name of the class to look for.
* @ant.attribute group="oneof"
*/
public void setClass(String classname) {
this.classname = classname;
}
/**
* the property to fill with the URL of the resource or class
* @param property the property to be set.
* @ant.attribute group="required"
*/
public void setProperty(String property) {
this.property = property;
}
}