001 package nl.cwi.sen1.tide;
002
003 import java.awt.Font;
004 import java.io.File;
005 import java.io.FileInputStream;
006 import java.io.FileOutputStream;
007 import java.io.IOException;
008 import java.io.InputStream;
009 import java.io.OutputStream;
010 import java.util.ArrayList;
011 import java.util.Iterator;
012 import java.util.List;
013 import java.util.Properties;
014
015 public class PreferenceSet {
016 public static final String PREFS_FILE = ".tiderc";
017
018 private List<String> preferenceNames;
019 private Properties preferences;
020 private List<PreferenceListener> listeners;
021
022 private boolean is_clean;
023
024 public PreferenceSet(Properties defaults) {
025 preferenceNames = new ArrayList<String>();
026 preferences = new Properties(defaults);
027 listeners = new ArrayList<PreferenceListener>();
028 }
029
030 public void registerPreference(String name) {
031 preferenceNames.add(name);
032 }
033
034 public Iterator<String> preferenceNameIterator(String prefix) {
035 return new PreferenceIterator(prefix, preferenceNames);
036 }
037
038 public void addPreferenceListener(PreferenceListener listener) {
039 listeners.add(listener);
040 }
041
042 public void removePreferenceListener(PreferenceListener listener) {
043 listeners.remove(listener);
044 }
045
046 public void firePreferenceChanged(String name, String oldValue,
047 String newValue) {
048 System.out.println("preference changed: " + name + " from " + oldValue
049 + " into " + newValue);
050
051 Iterator<PreferenceListener> iter = listeners.iterator();
052 while (iter.hasNext()) {
053 PreferenceListener listener = iter.next();
054 listener.preferenceChanged(this, name, oldValue, newValue);
055 }
056 }
057
058 public void firePreferencesChanged() {
059 Iterator<PreferenceListener> iter = listeners.iterator();
060 while (iter.hasNext()) {
061 PreferenceListener listener = iter.next();
062 listener.preferencesChanged(this);
063 }
064 }
065
066 public void firePreferencesStatusChanged(boolean new_status) {
067 Iterator<PreferenceListener> iter = listeners.iterator();
068 while (iter.hasNext()) {
069 PreferenceListener listener = iter.next();
070 listener.preferencesStatusChanged(this, new_status);
071 }
072 }
073
074 public void loadPreferences() throws IOException {
075 String path = System.getProperty("user.home");
076 File file = new File(path, PREFS_FILE);
077 FileInputStream input = new FileInputStream(file);
078 loadPreferences(input);
079 }
080
081 public void loadPreferences(InputStream input) throws IOException {
082 preferences.load(input);
083 firePreferencesChanged();
084 }
085
086 public void savePreferences() throws IOException {
087 FileOutputStream stream = new FileOutputStream(PREFS_FILE);
088 savePreferences(stream);
089 }
090
091 public void savePreferences(OutputStream stream) throws IOException {
092 preferences.store(stream, "Tide Preferences");
093 setClean();
094 }
095
096 public void setClean() {
097 setStatus(true);
098 }
099
100 private void setStatus(boolean status) {
101 if (is_clean != status) {
102 is_clean = status;
103 firePreferencesStatusChanged(is_clean);
104 }
105 }
106
107 public void setPreference(String name, String value) {
108 String oldValue = (String) preferences.setProperty(name, value);
109 if (oldValue == null || !oldValue.equals(value)) {
110 firePreferenceChanged(name, oldValue, value);
111 setStatus(false);
112 }
113 }
114
115 public void setBooleanPreference(String name, boolean value) {
116 setPreference(name, new Boolean(value).toString());
117 }
118
119 public void setIntegerPreference(String name, int value) {
120 setPreference(name, new Integer(value).toString());
121 }
122
123 public String getPreference(String name) {
124 return preferences.getProperty(name);
125 }
126
127 public Boolean getBooleanPreference(String name) {
128 String value = getPreference(name);
129 if (value == null) {
130 return null;
131 }
132
133 return Boolean.valueOf(value);
134 }
135
136 public Integer getIntegerPreference(String name) {
137 String value = getPreference(name);
138 if (value == null) {
139 return null;
140 }
141
142 return Integer.valueOf(value);
143 }
144
145 public Font getFontPreference(String name) {
146 return Font.decode(getPreference(name));
147 }
148 }
149
150 class PreferenceIterator implements Iterator<String> {
151 private String prefix;
152 private List<String> names;
153 private int index;
154 private String curName;
155
156 public PreferenceIterator(String prefix, List<String> names) {
157 this.prefix = prefix;
158 this.names = names;
159
160 index = 0;
161
162 forward();
163 }
164
165 private void forward() {
166 while (index < names.size()) {
167 curName = names.get(index);
168 if (curName.startsWith(prefix)) {
169 break;
170 }
171 }
172 }
173
174 public boolean hasNext() {
175 return index < names.size();
176 }
177
178 public String next() {
179 String name = curName;
180 index++;
181 forward();
182
183 return name;
184 }
185
186 public void remove() {
187 throw new UnsupportedOperationException();
188 }
189 }