/*******************************************************************************
* Copyright (c) 2000, 2005 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.jface.preference;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Properties;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.jface.util.Assert;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.ListenerList;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.jface.util.SafeRunnable;
/**
* A concrete preference store implementation based on an internal
* <code>java.util.Properties</code> object, with support for persisting the
* non-default preference values to files or streams.
* <p>
* This class was not designed to be subclassed.
* </p>
*
* @see IPreferenceStore
*/
public class PreferenceStore implements IPersistentPreferenceStore {
/**
* List of registered listeners (element type:
* <code>IPropertyChangeListener</code>). These listeners are to be
* informed when the current value of a preference changes.
*/
private ListenerList listeners = new ListenerList();
/**
* The mapping from preference name to preference value (represented as
* strings).
*/
private Properties properties;
/**
* The mapping from preference name to default preference value (represented
* as strings); <code>null</code> if none.
*/
private Properties defaultProperties;
/**
* Indicates whether a value as been changed by <code>setToDefault</code>
* or <code>setValue</code>; initially <code>false</code>.
*/
private boolean dirty = false;
/**
* The file name used by the <code>load</code> method to load a property
* file. This filename is used to save the properties file when
* <code>save</code> is called.
*/
private String filename;
/**
* Creates an empty preference store.
* <p>
* Use the methods <code>load(InputStream)</code> and
* <code>save(InputStream)</code> to load and store this preference store.
* </p>
*
* @see #load(InputStream)
* @see #save(OutputStream, String)
*/
public PreferenceStore() {
defaultProperties = new Properties();
properties = new Properties(defaultProperties);
}
/**
* Creates an empty preference store that loads from and saves to the a
* file.
* <p>
* Use the methods <code>load()</code> and <code>save()</code> to load
* and store this preference store.
* </p>
*
* @param filename
* the file name
* @see #load()
* @see #save()
*/
public PreferenceStore(String filename) {
this();
Assert.isNotNull(filename);
this.filename = filename;
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void addPropertyChangeListener(IPropertyChangeListener listener) {
listeners.add(listener);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public boolean contains(String name) {
return (properties.containsKey(name) || defaultProperties
.containsKey(name));
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void firePropertyChangeEvent(String name, Object oldValue,
Object newValue) {
final Object[] finalListeners = this.listeners.getListeners();
// Do we need to fire an event.
if (finalListeners.length > 0
&& (oldValue == null || !oldValue.equals(newValue))) {
final PropertyChangeEvent pe = new PropertyChangeEvent(this, name,
oldValue, newValue);
for (int i = 0; i < finalListeners.length; ++i) {
final IPropertyChangeListener l = (IPropertyChangeListener) finalListeners[i];
SafeRunnable.run(new SafeRunnable(JFaceResources.getString("PreferenceStore.changeError")) { //$NON-NLS-1$
public void run() {
l.propertyChange(pe);
}
});
}
}
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public boolean getBoolean(String name) {
return getBoolean(properties, name);
}
/**
* Helper function: gets boolean for a given name.
*
* @param p
* @param name
* @return boolean
*/
private boolean getBoolean(Properties p, String name) {
String value = p != null ? p.getProperty(name) : null;
if (value == null)
return BOOLEAN_DEFAULT_DEFAULT;
if (value.equals(IPreferenceStore.TRUE))
return true;
return false;
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public boolean getDefaultBoolean(String name) {
return getBoolean(defaultProperties, name);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public double getDefaultDouble(String name) {
return getDouble(defaultProperties, name);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public float getDefaultFloat(String name) {
return getFloat(defaultProperties, name);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public int getDefaultInt(String name) {
return getInt(defaultProperties, name);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public long getDefaultLong(String name) {
return getLong(defaultProperties, name);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public String getDefaultString(String name) {
return getString(defaultProperties, name);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public double getDouble(String name) {
return getDouble(properties, name);
}
/**
* Helper function: gets double for a given name.
*
* @param p
* @param name
* @return double
*/
private double getDouble(Properties p, String name) {
String value = p != null ? p.getProperty(name) : null;
if (value == null)
return DOUBLE_DEFAULT_DEFAULT;
double ival = DOUBLE_DEFAULT_DEFAULT;
try {
ival = new Double(value).doubleValue();
} catch (NumberFormatException e) {
}
return ival;
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public float getFloat(String name) {
return getFloat(properties, name);
}
/**
* Helper function: gets float for a given name.
* @param p
* @param name
* @return float
*/
private float getFloat(Properties p, String name) {
String value = p != null ? p.getProperty(name) : null;
if (value == null)
return FLOAT_DEFAULT_DEFAULT;
float ival = FLOAT_DEFAULT_DEFAULT;
try {
ival = new Float(value).floatValue();
} catch (NumberFormatException e) {
}
return ival;
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public int getInt(String name) {
return getInt(properties, name);
}
/**
* Helper function: gets int for a given name.
* @param p
* @param name
* @return int
*/
private int getInt(Properties p, String name) {
String value = p != null ? p.getProperty(name) : null;
if (value == null)
return INT_DEFAULT_DEFAULT;
int ival = 0;
try {
ival = Integer.parseInt(value);
} catch (NumberFormatException e) {
}
return ival;
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public long getLong(String name) {
return getLong(properties, name);
}
/**
* Helper function: gets long for a given name.
* @param p
* @param name
* @return
*/
private long getLong(Properties p, String name) {
String value = p != null ? p.getProperty(name) : null;
if (value == null)
return LONG_DEFAULT_DEFAULT;
long ival = LONG_DEFAULT_DEFAULT;
try {
ival = Long.parseLong(value);
} catch (NumberFormatException e) {
}
return ival;
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public String getString(String name) {
return getString(properties, name);
}
/**
* Helper function: gets string for a given name.
* @param p
* @param name
* @return
*/
private String getString(Properties p, String name) {
String value = p != null ? p.getProperty(name) : null;
if (value == null)
return STRING_DEFAULT_DEFAULT;
return value;
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public boolean isDefault(String name) {
return (!properties.containsKey(name) && defaultProperties
.containsKey(name));
}
/**
* Prints the contents of this preference store to the given print stream.
*
* @param out
* the print stream
*/
public void list(PrintStream out) {
properties.list(out);
}
/**
* Prints the contents of this preference store to the given print writer.
*
* @param out
* the print writer
*/
public void list(PrintWriter out) {
properties.list(out);
}
/**
* Loads this preference store from the file established in the constructor
* <code>PreferenceStore(java.lang.String)</code> (or by
* <code>setFileName</code>). Default preference values are not affected.
*
* @exception java.io.IOException
* if there is a problem loading this store
*/
public void load() throws IOException {
if (filename == null)
throw new IOException("File name not specified");//$NON-NLS-1$
FileInputStream in = new FileInputStream(filename);
load(in);
in.close();
}
/**
* Loads this preference store from the given input stream. Default
* preference values are not affected.
*
* @param in
* the input stream
* @exception java.io.IOException
* if there is a problem loading this store
*/
public void load(InputStream in) throws IOException {
properties.load(in);
dirty = false;
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public boolean needsSaving() {
return dirty;
}
/**
* Returns an enumeration of all preferences known to this store which have
* current values other than their default value.
*
* @return an array of preference names
*/
public String[] preferenceNames() {
ArrayList list = new ArrayList();
Enumeration it = properties.propertyNames();
while (it.hasMoreElements()) {
list.add(it.nextElement());
}
return (String[]) list.toArray(new String[list.size()]);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void putValue(String name, String value) {
String oldValue = getString(name);
if (oldValue == null || !oldValue.equals(value)) {
setValue(properties, name, value);
dirty = true;
}
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void removePropertyChangeListener(IPropertyChangeListener listener) {
listeners.remove(listener);
}
/**
* Saves the non-default-valued preferences known to this preference store
* to the file from which they were originally loaded.
*
* @exception java.io.IOException
* if there is a problem saving this store
*/
public void save() throws IOException {
if (filename == null)
throw new IOException("File name not specified");//$NON-NLS-1$
FileOutputStream out = null;
try {
out = new FileOutputStream(filename);
save(out, null);
} finally {
if (out != null)
out.close();
}
}
/**
* Saves this preference store to the given output stream. The given string
* is inserted as header information.
*
* @param out
* the output stream
* @param header
* the header
* @exception java.io.IOException
* if there is a problem saving this store
*/
public void save(OutputStream out, String header) throws IOException {
properties.store(out, header);
dirty = false;
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void setDefault(String name, double value) {
setValue(defaultProperties, name, value);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void setDefault(String name, float value) {
setValue(defaultProperties, name, value);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void setDefault(String name, int value) {
setValue(defaultProperties, name, value);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void setDefault(String name, long value) {
setValue(defaultProperties, name, value);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void setDefault(String name, String value) {
setValue(defaultProperties, name, value);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void setDefault(String name, boolean value) {
setValue(defaultProperties, name, value);
}
/**
* Sets the name of the file used when loading and storing this preference
* store.
* <p>
* Afterward, the methods <code>load()</code> and <code>save()</code>
* can be used to load and store this preference store.
* </p>
*
* @param name the file name
* @see #load()
* @see #save()
*/
public void setFilename(String name) {
filename = name;
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void setToDefault(String name) {
Object oldValue = properties.get(name);
properties.remove(name);
dirty = true;
Object newValue = null;
if (defaultProperties != null)
newValue = defaultProperties.get(name);
firePropertyChangeEvent(name, oldValue, newValue);
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void setValue(String name, double value) {
double oldValue = getDouble(name);
if (oldValue != value) {
setValue(properties, name, value);
dirty = true;
firePropertyChangeEvent(name, new Double(oldValue), new Double(
value));
}
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void setValue(String name, float value) {
float oldValue = getFloat(name);
if (oldValue != value) {
setValue(properties, name, value);
dirty = true;
firePropertyChangeEvent(name, new Float(oldValue), new Float(value));
}
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void setValue(String name, int value) {
int oldValue = getInt(name);
if (oldValue != value) {
setValue(properties, name, value);
dirty = true;
firePropertyChangeEvent(name, new Integer(oldValue), new Integer(
value));
}
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void setValue(String name, long value) {
long oldValue = getLong(name);
if (oldValue != value) {
setValue(properties, name, value);
dirty = true;
firePropertyChangeEvent(name, new Long(oldValue), new Long(value));
}
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void setValue(String name, String value) {
String oldValue = getString(name);
if (oldValue == null || !oldValue.equals(value)) {
setValue(properties, name, value);
dirty = true;
firePropertyChangeEvent(name, oldValue, value);
}
}
/*
* (non-Javadoc) Method declared on IPreferenceStore.
*/
public void setValue(String name, boolean value) {
boolean oldValue = getBoolean(name);
if (oldValue != value) {
setValue(properties, name, value);
dirty = true;
firePropertyChangeEvent(name, new Boolean(oldValue), new Boolean(
value));
}
}
/**
* Helper method: sets value for a given name.
* @param p
* @param name
* @param value
*/
private void setValue(Properties p, String name, double value) {
Assert.isTrue(p != null);
p.put(name, Double.toString(value));
}
/**
* Helper method: sets value for a given name.
* @param p
* @param name
* @param value
*/
private void setValue(Properties p, String name, float value) {
Assert.isTrue(p != null);
p.put(name, Float.toString(value));
}
/**
* Helper method: sets value for a given name.
* @param p
* @param name
* @param value
*/
private void setValue(Properties p, String name, int value) {
Assert.isTrue(p != null);
p.put(name, Integer.toString(value));
}
/**
* Helper method: sets the value for a given name.
* @param p
* @param name
* @param value
*/
private void setValue(Properties p, String name, long value) {
Assert.isTrue(p != null);
p.put(name, Long.toString(value));
}
/**
* Helper method: sets the value for a given name.
* @param p
* @param name
* @param value
*/
private void setValue(Properties p, String name, String value) {
Assert.isTrue(p != null && value != null);
p.put(name, value);
}
/**
* Helper method: sets the value for a given name.
* @param p
* @param name
* @param value
*/
private void setValue(Properties p, String name, boolean value) {
Assert.isTrue(p != null);
p.put(name, value == true ? IPreferenceStore.TRUE
: IPreferenceStore.FALSE);
}
}
