Java tutorial
/* * 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.synapse.securevault.commons; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.synapse.securevault.SecureVaultException; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.util.Properties; /** * TODO - This is a copy of class in synapse commons */ public class MiscellaneousUtil { private static Log log = LogFactory.getLog(MiscellaneousUtil.class); private MiscellaneousUtil() { } /** * Helper method to get the value of the property from a given property bag * * @param properties The property collection * @param name The name of the property * @param defaultValue The default value for the property * @return The value of the property if it is found , otherwise , default value */ public static String getProperty(Properties properties, String name, String defaultValue) { String result = properties.getProperty(name); if ((result == null || result.length() == 0) && defaultValue != null) { if (log.isDebugEnabled()) { log.debug( "The name with ' " + name + " ' cannot be found. " + "Using default value " + defaultValue); } result = defaultValue; } if (result != null) { return result.trim(); } else { return defaultValue; } } /** * Helper method to get the value of the property from a given property bag * This method will return a value with the type equal to the type * given by the Class type parameter. Therefore, The user of this method * can ensure that he is get what he request * * @param properties Properties bag * @param name Name of the property * @param defaultValue Default value * @param type Expected Type using Class * @return Value corresponding to the given property name */ @SuppressWarnings({ "TypeParameterExplicitlyExtendsObject", "unchecked" }) public static <T extends Object> T getProperty(Properties properties, String name, T defaultValue, Class<? extends T> type) { String result = properties.getProperty(name); if (result == null && defaultValue != null) { if (log.isDebugEnabled()) { log.debug( "The name with ' " + name + " ' cannot be found. " + "Using default value " + defaultValue); } return defaultValue; } if (result == null || type == null) { return null; } if (String.class.equals(type)) { return (T) result; } else if (Boolean.class.equals(type)) { return (T) Boolean.valueOf(Boolean.parseBoolean(result)); } else if (Integer.class.equals(type)) { return (T) Integer.valueOf(Integer.parseInt(result)); } else if (Long.class.equals(type)) { return (T) Long.valueOf(Long.parseLong(result)); } else { handleException("Unsupported type: " + type); } return null; } /** * Loads the properties from a given property file path * * @param filePath Path of the property file * @return Properties loaded from given file */ public static Properties loadProperties(String filePath) { Properties properties = new Properties(); ClassLoader cl = Thread.currentThread().getContextClassLoader(); if (log.isDebugEnabled()) { log.debug("Loading a file ' " + filePath + " ' from classpath"); } InputStream in = cl.getResourceAsStream(filePath); if (in == null) { if (log.isDebugEnabled()) { log.debug("Unable to load file ' " + filePath + " '"); } filePath = "conf" + File.separatorChar + filePath; if (log.isDebugEnabled()) { log.debug("Loading a file ' " + filePath + " ' from classpath"); } in = cl.getResourceAsStream(filePath); if (in == null) { if (log.isDebugEnabled()) { log.debug("Unable to load file ' " + filePath + " '"); } } } if (in != null) { try { properties.load(in); } catch (IOException e) { String msg = "Error loading properties from a file at :" + filePath; log.error(msg, e); throw new SecureVaultException(msg, e); } } return properties; } public static byte[] asBytes(InputStream in) { ByteArrayOutputStream out = new ByteArrayOutputStream(); byte[] buffer = new byte[1024]; int len; try { while ((len = in.read(buffer)) >= 0) out.write(buffer, 0, len); } catch (IOException e) { throw new SecureVaultException("Error during converting a inputstream " + "into a bytearray ", e, log); } finally { if (in != null) { try { in.close(); } catch (IOException ignored) { } } try { out.close(); } catch (IOException ignored) { } } return out.toByteArray(); } /** * Helper methods for handle errors. * * @param msg The error message */ private static void handleException(String msg) { log.error(msg); throw new SecureVaultException(msg); } }