Java tutorial
/* * Copyright (C) 2013 Ustream Inc. * author chaotx <lombai.ferenc@ustream.tv> * * For the full copyright and license information, please view the LICENSE * file that was distributed with this source code. */ package com.robin.utilities.config; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.util.Properties; import org.apache.commons.lang.SystemUtils; public final class RobinConfiguration implements Configuration { private static final String BUILD_PROPERTIES = "#basedir#/build.properties"; private static final String ROBIN_PROPERTIES = "#basedir#/Robin.properties"; private Properties properties; private File baseDir; public RobinConfiguration() { properties = System.getProperties(); baseDir = new File(properties.getProperty("basedir")); if (baseDir == null) { baseDir = new File("."); } addConfigFile(ROBIN_PROPERTIES); addConfigFileIfExists(BUILD_PROPERTIES); if (properties.getProperty(ConfigParams.MIN_DEVICE_TO_USE) == null) { properties.setProperty(ConfigParams.MIN_DEVICE_TO_USE, "1"); } } @Override public String getValue(final String key) { String result = properties.getProperty(key); if (null == result) { throw new ConfigurationNotFoundException(key); } return result; } @Override public void addConfigFile(final String filename) { addConfigFile(new File(replaceBaseDirInString(filename))); } /** * Add Config File. * @param filename Name of the Configuration file */ public void addConfigFile(final File filename) { try { loadPropertiesFromPath(filename); } catch (IOException e) { throw new ConfigurationCantBeLoadedException(filename.getPath()); } } private void loadPropertiesFromPath(final File file) throws IOException { Properties propertiesFromFile = new Properties(); propertiesFromFile.load(getStream(file)); for (String key : propertiesFromFile.stringPropertyNames()) { String value = replaceBaseDirInString(propertiesFromFile.getProperty(key)); properties.setProperty(key, value); } } @Override public void addConfigFileIfExists(final String filename) { addConfigFileIfExists(new File(replaceBaseDirInString(filename))); } public void addConfigFileIfExists(final File filename) { if (filename.exists()) { addConfigFile(filename); } } private FileInputStream getStream(final File file) { try { FileInputStream is = new FileInputStream(file); return is; } catch (FileNotFoundException e) { throw new ConfigurationFileNotFoundException(file.getPath()); } } private String replaceBaseDirInString(final String path) { String out = path.replace("#basedir#", baseDir.getPath()); if (SystemUtils.IS_OS_WINDOWS) { out = separatorsToWindows(out); } return out; } private String separatorsToWindows(final String input) { String out = input.replaceAll("[/]", "\\\\"); return out; } }