com.beust.jcommander.defaultprovider.PropertyFileDefaultProvider Maven / Gradle / Ivy
/**
* Copyright (C) 2010 the original author or authors.
* See the notice.md file distributed with this work for additional
* information regarding copyright ownership.
*
* 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 com.beust.jcommander.defaultprovider;
import com.beust.jcommander.IDefaultProvider;
import com.beust.jcommander.ParameterException;
import java.io.IOException;
import java.net.URL;
import java.util.Properties;
/**
* A default provider that reads its default values from a property file.
*
* @author cbeust
*/
public class PropertyFileDefaultProvider implements IDefaultProvider {
public static final String DEFAULT_FILE_NAME = "jcommander.properties";
private Properties properties;
public PropertyFileDefaultProvider() {
init(DEFAULT_FILE_NAME);
}
public PropertyFileDefaultProvider(String fileName) {
init(fileName);
}
private void init(String fileName) {
try {
properties = new Properties();
URL url = ClassLoader.getSystemResource(fileName);
if (url != null) {
properties.load(url.openStream());
} else {
throw new ParameterException("Could not find property file: " + fileName
+ " on the class path");
}
}
catch (IOException e) {
throw new ParameterException("Could not open property file: " + fileName);
}
}
public String getDefaultValueFor(String optionName) {
int index = 0;
while (index < optionName.length() && ! Character.isLetterOrDigit(optionName.charAt(index))) {
index++;
}
String key = optionName.substring(index);
return properties.getProperty(key);
}
}