preferencestore.java

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     * 
     * @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) {
        removeListenerObject(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);
    }
}