| /** |
| * 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.aries.blueprint.ext; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.net.URL; |
| import java.util.Dictionary; |
| import java.util.Enumeration; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Properties; |
| |
| import org.apache.aries.blueprint.ext.evaluator.PropertyEvaluator; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Property placeholder that looks for properties in the System properties. |
| * |
| * @version $Rev$, $Date$ |
| */ |
| public class PropertyPlaceholder extends AbstractPropertyPlaceholder { |
| |
| public enum SystemProperties { |
| never, |
| fallback, |
| override |
| } |
| |
| private static final Logger LOGGER = LoggerFactory.getLogger(PropertyPlaceholder.class); |
| |
| private Map defaultProperties; |
| private Properties properties; |
| private List<URL> locations; |
| private boolean ignoreMissingLocations; |
| private SystemProperties systemProperties = SystemProperties.fallback; |
| private PropertyEvaluator evaluator = null; |
| |
| public Map getDefaultProperties() { |
| return defaultProperties; |
| } |
| |
| public void setDefaultProperties(Map defaultProperties) { |
| this.defaultProperties = defaultProperties; |
| } |
| |
| public List<URL> getLocations() { |
| return locations; |
| } |
| |
| public void setLocations(List<URL> locations) { |
| this.locations = locations; |
| } |
| |
| public boolean isIgnoreMissingLocations() { |
| return ignoreMissingLocations; |
| } |
| |
| public void setIgnoreMissingLocations(boolean ignoreMissingLocations) { |
| this.ignoreMissingLocations = ignoreMissingLocations; |
| } |
| |
| public SystemProperties getSystemProperties() { |
| return systemProperties; |
| } |
| |
| public void setSystemProperties(SystemProperties systemProperties) { |
| this.systemProperties = systemProperties; |
| } |
| |
| public PropertyEvaluator getEvaluator() { |
| return evaluator; |
| } |
| |
| public void setEvaluator(PropertyEvaluator evaluator) { |
| this.evaluator = evaluator; |
| } |
| |
| public void init() throws Exception { |
| properties = new Properties(); |
| if (locations != null) { |
| for (URL url : locations) { |
| InputStream is = null; |
| try { |
| is = url.openStream(); |
| } catch (IOException e) { |
| if (ignoreMissingLocations) { |
| LOGGER.debug("Unable to load properties from url " + url + " while ignoreMissingLocations is set to true"); |
| } else { |
| throw e; |
| } |
| } |
| if (is != null) { |
| try { |
| properties.load(is); |
| } finally { |
| is.close(); |
| } |
| } |
| } |
| } |
| } |
| |
| protected String getProperty(String val) { |
| LOGGER.debug("Retrieving property {}", val); |
| Object v = null; |
| if (v == null && systemProperties == SystemProperties.override) { |
| v = getSystemProperty(val); |
| if (v != null) { |
| LOGGER.debug("Found system property {} with value {}", val, v); |
| } |
| } |
| if (v == null && properties != null) { |
| v = properties.getProperty(val); |
| if (v != null) { |
| LOGGER.debug("Found property {} from locations with value {}", val, v); |
| } |
| } |
| if (v == null && systemProperties == SystemProperties.fallback) { |
| v = getSystemProperty(val); |
| if (v != null) { |
| LOGGER.debug("Found system property {} with value {}", val, v); |
| } |
| } |
| if (v == null && defaultProperties != null) { |
| v = defaultProperties.get(val); |
| if (v != null) { |
| LOGGER.debug("Retrieved property {} value from defaults {}", val, v); |
| } |
| } |
| if (v == null) { |
| LOGGER.debug("Property {} not found", val); |
| } |
| return v != null ? v.toString() : null; |
| } |
| |
| protected String getSystemProperty(String val) { |
| if (val.startsWith("env:")) { |
| return System.getenv(val.substring("env:".length())); |
| } |
| return System.getProperty(val); |
| } |
| |
| @Override |
| protected String retrieveValue(String expression) { |
| LOGGER.debug("Retrieving Value from expression: {}", expression); |
| |
| if (evaluator == null) { |
| return super.retrieveValue(expression); |
| } else { |
| return evaluator.evaluate(expression, new Dictionary<String, String>(){ |
| @Override |
| public String get(Object key) { |
| return getProperty((String) key); |
| } |
| |
| // following are not important |
| @Override |
| public String put(String key, String value) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| public Enumeration<String> elements() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| public boolean isEmpty() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| public Enumeration<String> keys() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| public String remove(Object key) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| public int size() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| }); |
| } |
| |
| } |
| |
| |
| } |