org.apache.tools.ant.input.PropertyFileInputHandler 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.input;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Properties;
import org.apache.tools.ant.BuildException;
/**
* Reads input from a property file, the file name is read from the
* system property ant.input.properties, the prompt is the key for input.
*
* @since Ant 1.5
*/
public class PropertyFileInputHandler implements InputHandler {
private Properties props = null;
/**
* Name of the system property we expect to hold the file name.
*/
public static final String FILE_NAME_KEY = "ant.input.properties";
/**
* Empty no-arg constructor.
*/
public PropertyFileInputHandler() {
}
/**
* Picks up the input from a property, using the prompt as the
* name of the property.
* @param request an input request.
*
* @exception BuildException if no property of that name can be found.
*/
public void handleInput(InputRequest request) throws BuildException {
readProps();
Object o = props.get(request.getPrompt());
if (o == null) {
throw new BuildException("Unable to find input for \'"
+ request.getPrompt() + "\'");
}
request.setInput(o.toString());
if (!request.isInputValid()) {
throw new BuildException("Found invalid input " + o
+ " for \'" + request.getPrompt() + "\'");
}
}
/**
* Reads the properties file if it hasn't already been read.
*/
private synchronized void readProps() throws BuildException {
if (props == null) {
String propsFile = System.getProperty(FILE_NAME_KEY);
if (propsFile == null) {
throw new BuildException("System property "
+ FILE_NAME_KEY
+ " for PropertyFileInputHandler not"
+ " set");
}
props = new Properties();
try {
props.load(Files.newInputStream(Paths.get(propsFile)));
} catch (IOException e) {
throw new BuildException("Couldn't load " + propsFile, e);
}
}
}
}