001 /*
002 * Copyright (C) 2012 eXo Platform SAS.
003 *
004 * This is free software; you can redistribute it and/or modify it
005 * under the terms of the GNU Lesser General Public License as
006 * published by the Free Software Foundation; either version 2.1 of
007 * the License, or (at your option) any later version.
008 *
009 * This software is distributed in the hope that it will be useful,
010 * but WITHOUT ANY WARRANTY; without even the implied warranty of
011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012 * Lesser General Public License for more details.
013 *
014 * You should have received a copy of the GNU Lesser General Public
015 * License along with this software; if not, write to the Free
016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
018 */
019
020 package org.crsh.plugin;
021
022 import java.util.HashMap;
023 import java.util.Map;
024 import java.util.logging.Level;
025 import java.util.logging.Logger;
026
027 /** @author <a href="mailto:julien.viet@exoplatform.com">Julien Viet</a> */
028 class PropertyManager {
029
030 /** . */
031 private static final Logger log = Logger.getLogger(PropertyManager.class.getName());
032
033 /** . */
034 private final Map<String, Property<?>> properties;
035
036 PropertyManager() {
037 this.properties = new HashMap<String, Property<?>>();
038 }
039
040 /**
041 * Returns a property value or null if it cannot be found.
042 *
043 * @param desc the property descriptor
044 * @param <T> the property parameter type
045 * @return the property value
046 * @throws NullPointerException if the descriptor argument is null
047 */
048 public <T> T getPropertyValue(PropertyDescriptor<T> desc) throws NullPointerException {
049 if (desc == null) {
050 throw new NullPointerException();
051 }
052 Property<T> property = getProperty(desc.getName(), desc.getType());
053 return property != null ? property.getValue() : null;
054 }
055
056 /**
057 * Returns a property or null if it cannot be found.
058 *
059 * @param desc the property descriptor
060 * @param <T> the property parameter type
061 * @return the property object
062 * @throws NullPointerException if the descriptor argument is null
063 */
064 public <T> Property<T> getProperty(PropertyDescriptor<T> desc) throws NullPointerException {
065 if (desc == null) {
066 throw new NullPointerException();
067 }
068 return getProperty(desc.getName(), desc.getType());
069 }
070
071 /**
072 * Returns a property or null if it cannot be found.
073 *
074 * @param propertyName the name of the property
075 * @param type the property type
076 * @param <T> the property parameter type
077 * @return the property object
078 * @throws NullPointerException if any argument is null
079 */
080 private <T> Property<T> getProperty(String propertyName, Class<T> type) throws NullPointerException {
081 if (propertyName == null) {
082 throw new NullPointerException("No null property name accepted");
083 }
084 if (type == null) {
085 throw new NullPointerException("No null property type accepted");
086 }
087 Property<?> property = properties.get(propertyName);
088 if (property != null) {
089 PropertyDescriptor<?> descriptor = property.getDescriptor();
090 if (type.equals(descriptor.getType())) {
091 return (Property<T>)property;
092 }
093 }
094 return null;
095 }
096
097 /**
098 * Set a context property to a new value. If the provided value is null, then the property is removed.
099 *
100 * @param desc the property descriptor
101 * @param value the property value
102 * @param <T> the property parameter type
103 * @throws NullPointerException if the descriptor argument is null
104 */
105 <T> void setProperty(PropertyDescriptor<T> desc, T value) throws NullPointerException {
106 if (desc == null) {
107 throw new NullPointerException("No null descriptor allowed");
108 }
109 if (value == null) {
110 log.log(Level.FINE, "Removing property " + desc.name);
111 properties.remove(desc.getName());
112 } else {
113 Property<T> property = new Property<T>(desc, value);
114 log.log(Level.FINE, "Setting property " + desc.name + " to value " + property.getValue());
115 properties.put(desc.getName(), property);
116 }
117 }
118
119 /**
120 * Set a context property to a new value.
121 *
122 * @param desc the property descriptor
123 * @param value the property value
124 * @param <T> the property parameter type
125 * @throws NullPointerException if the descriptor argument or the value is null
126 * @throws IllegalArgumentException if the string value cannot be converted to the property type
127 */
128 <T> void parseProperty(PropertyDescriptor<T> desc, String value) throws NullPointerException, IllegalArgumentException {
129 if (desc == null) {
130 throw new NullPointerException("No null descriptor allowed");
131 }
132 if (value == null) {
133 throw new NullPointerException("No null value accepted");
134 } else {
135 Property<T> property = desc.toProperty(value);
136 log.log(Level.FINE, "Setting property " + desc.name + " to value " + property.getValue());
137 properties.put(desc.getName(), property);
138 }
139 }
140 }