com.iw.plugins.spindle.core.eclipse.ProjectPreferenceStore.java Source code

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Here is the source code for com.iw.plugins.spindle.core.eclipse.ProjectPreferenceStore.java

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/*******************************************************************************
 * Copyright (c) 2000, 2004 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *    glongman@gmail.com - tweaks for Spindle.
 *******************************************************************************/
package com.iw.plugins.spindle.core.eclipse;

import java.io.File;
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.Iterator;
import java.util.Properties;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IProject;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.jface.preference.IPersistentPreferenceStore;
import org.eclipse.jface.preference.IPreferenceStore;
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 com.iw.plugins.spindle.core.TapestryCore;
import com.iw.plugins.spindle.core.util.eclipse.EclipsePluginUtils;

/**
 * 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>
 * Changed by GWL to use another preference store to provide defaults
 * </p>
 * 
 * @see IPreferenceStore
 */
public class ProjectPreferenceStore implements IPersistentPreferenceStore {

    public static ProjectPreferenceStore createEmptyStore(IPreferenceStore backingStore) {
        Assert.isNotNull(backingStore);
        return new ProjectPreferenceStore("", backingStore);
    }

    public static ProjectPreferenceStore getStore(IProject project, String filename,
            IPreferenceStore defaultStore) {
        Assert.isNotNull(project);
        Assert.isNotNull(defaultStore);

        ProjectPreferenceStore store = new ProjectPreferenceStore("", defaultStore);

        IFile dataFile = project.getFile(filename);

        String fullname;
        if (dataFile.exists()) {
            fullname = dataFile.getLocation().toOSString();
        } else {
            fullname = project.getLocation().toOSString() + File.separator + filename;
        }

        store.setFilename(fullname);

        if (dataFile.exists()) {
            try {
                store.load();
                for (Iterator iter = store.properties.keySet().iterator(); iter.hasNext();) {
                    String name = (String) iter.next();
                    String value = store.properties.getProperty(name);

                    if (store.backingStore.getString(name).equals(value))
                        store.properties.remove(name);
                }
            } catch (IOException e) {
                TapestryCore.log(e);
                MessageDialog.openError(EclipsePluginUtils.getActiveWorkbenchShell(), "Error",
                        "an error occured reading project prefs: " + e.getMessage());
            }
        }
        return store;
    }

    /**
     * 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 backing store that provides default values.
     */
    private IPreferenceStore backingStore;
    /**
     * 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 ProjectPreferenceStore(String filename, IPreferenceStore defaultStore) {
        properties = new Properties(defaultProperties);
        backingStore = defaultStore;
        setFilename(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);
            //   FIXME: need to do this without dependency on
            // org.eclipse.core.runtime
            //      Platform.run(new
            // SafeRunnable(JFaceResources.getString("PreferenceStore.changeError"))
            // { //$NON-NLS-1$
            //         public void run() {
            for (int i = 0; i < finalListeners.length; ++i) {
                IPropertyChangeListener l = (IPropertyChangeListener) finalListeners[i];
                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 backingStore.getBoolean(name);
    }

    /*
     * (non-Javadoc) Method declared on IPreferenceStore.
     */
    public double getDefaultDouble(String name) {
        return backingStore.getDouble(name);
    }

    /*
     * (non-Javadoc) Method declared on IPreferenceStore.
     */
    public float getDefaultFloat(String name) {
        return backingStore.getFloat(name);
    }

    /*
     * (non-Javadoc) Method declared on IPreferenceStore.
     */
    public int getDefaultInt(String name) {
        return backingStore.getInt(name);
    }

    /*
     * (non-Javadoc) Method declared on IPreferenceStore.
     */
    public long getDefaultLong(String name) {
        return backingStore.getLong(name);
    }

    /*
     * (non-Javadoc) Method declared on IPreferenceStore.
     */
    public String getDefaultString(String name) {
        return backingStore.getString(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 backingStore.getDouble(name);
        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 backingStore.getFloat(name);
        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 backingStore.getInt(name);
        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 backingStore.getLong(name);
        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 backingStore.getString(name);
        return value;
    }

    /*
     * (non-Javadoc) Method declared on IPreferenceStore.
     */
    public boolean isDefault(String name) {
        if (!properties.containsKey(name))
            return true;

        String value = properties.getProperty(name, null);
        if (value == null)
            return true;

        return value.equals(backingStore.getString(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 enumeration = properties.propertyNames();
        while (enumeration.hasMoreElements()) {
            list.add(enumeration.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, "if empty, workspace defaults are used");
        } 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 (backingStore != null)
            newValue = backingStore.getString(name);
        // XXX this is hacked for String only
        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);
    }
}