Ant example source code file (Nice.java)

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Java - Ant tags/keywords

buildexception, buildexception, illegalargumentexception, integer, integer, nice, priority, string, string, task, the, the, thread, unable

The Nice.java source code

/*
 *  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;

import org.apache.tools.ant.Task;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.Project;

/**
 * A task to provide "nice-ness" to the current thread, and/or to
 * query the current value.
 * Examples:
 * <pre> <nice currentPriority="current.value" >

* Set <code>currentPriority to the current priority * <pre> <nice newPriority="10" >

* Raise the priority of the build process (But not forked programs) * <pre> <nice currentPriority="old" newPriority="3" >

* Lower the priority of the build process (But not forked programs), and save * the old value to the property <code>old. * * @ant.task name="nice" category="control" */ public class Nice extends Task { /** * the new priority */ private Integer newPriority; /** * the current priority */ private String currentPriority; /** * Execute the task * @exception BuildException if something goes wrong with the build */ public void execute() throws BuildException { Thread self = Thread.currentThread(); int priority = self.getPriority(); if (currentPriority != null) { String current = Integer.toString(priority); getProject().setNewProperty(currentPriority, current); } //if there is a new priority, and it is different, change it if (newPriority != null && priority != newPriority.intValue()) { try { self.setPriority(newPriority.intValue()); } catch (SecurityException e) { //catch permissions denial and keep going log("Unable to set new priority -a security manager is in the way", Project.MSG_WARN); } catch (IllegalArgumentException iae) { throw new BuildException("Priority out of range", iae); } } } /** * The name of a property to set to the value of the current * thread priority. Optional * @param currentPriority the property name. */ public void setCurrentPriority(String currentPriority) { this.currentPriority = currentPriority; } /** * the new priority, in the range 1-10. * @param newPriority the new priority value. */ public void setNewPriority(int newPriority) { if (newPriority < Thread.MIN_PRIORITY || newPriority > Thread.MAX_PRIORITY) { throw new BuildException("The thread priority is out of the range 1-10"); } this.newPriority = new Integer(newPriority); } }