moved to helma.util package from helma.objectmodel

src/helma/util/SystemProperties.java

@@ -0,0 +1,155 @@
+// Property.java
+// Copyright (c) Hannes Wallnöfer 1997-2000
+ 
+package helma.util;
+
+import java.util.*;
+import java.io.*;
+
+/**
+ *  A property dictionary that is updated from a property file each time the
+ *  file is modified. It is also case insensitive.
+ */
+ 
+public final class SystemProperties extends Properties {
+
+    private Properties props;        // wrapped properties
+    private Properties newProps;    // used while building up props
+    private Properties defaultProps;
+    private File file;
+    private long lastread, lastcheck;
+
+    final static long cacheTime = 1500l;
+
+
+    public SystemProperties () {
+	this (null, null);
+    }
+
+    public SystemProperties (InputStream in) {
+	this (null, null);
+	try {
+	    load (in);
+	} catch (Exception x) {
+	    System.err.println ("Error reading properties from file "+file+": "+x);
+	} finally {
+	    try {
+	        in.close ();
+	    } catch (Exception ignore) {}
+	}
+	lastread = System.currentTimeMillis ();
+    }	
+
+    public SystemProperties (String filename) {
+	this (filename, null);
+    }
+
+    public SystemProperties (Properties defaultProps) {
+	this (null, defaultProps);
+    }
+
+    public SystemProperties (String filename, Properties defaultProps) {
+ 	// System.err.println ("building sysprops with file "+filename+" and node "+node);
+	this.defaultProps = defaultProps;
+	props = defaultProps == null ?
+	        new Properties () : new Properties (defaultProps);
+
+	if (filename != null) {
+	    file = new File (filename);
+	    checkFile ();
+	}
+    }
+
+    public boolean wasModified () {
+	return file != null && file.exists() && file.lastModified () > lastread;
+    }
+
+    public long lastModified () {
+	return file == null || !file.exists () ? 0 : file.lastModified ();
+    }
+
+
+    private synchronized void checkFile () {
+	if (wasModified ()) {
+	    // IServer.getLogger().log ("Reading properties from file "+file);
+	    newProps = defaultProps == null ?
+	        new Properties () : new Properties (defaultProps);
+	    try {
+	        FileInputStream bpin = new FileInputStream (file);
+	        load (bpin);
+	        bpin.close ();
+	    } catch (Exception x) {
+	        System.err.println ("Error reading properties from file "+file+": "+x);
+	    }
+	    lastread = System.currentTimeMillis ();
+	    props = newProps;
+	    newProps = null;
+	}
+	lastcheck = System.currentTimeMillis ();
+    }
+
+    /*
+     * This should not be used directly if properties are read from file,
+     *  otherwise changes will be lost whe the file is next modified.
+     */
+    public Object put (Object key, Object value) {
+	if (newProps == null)
+	    return props.put (key.toString().toLowerCase(), value);
+	else
+	    return newProps.put (key.toString().toLowerCase(), value);
+    }
+
+    public Object get (Object key) {
+	return props.get (key);
+    }
+
+    public Object remove (Object key) {
+	return props.remove (key);
+    }
+
+    public void clear () {
+	props.clear ();
+    }
+
+    public boolean contains (Object obj) {
+	return props.contains (obj);
+    }
+
+    public boolean containsKey (Object key) {
+	return props.containsKey (key);
+    }
+
+    public boolean isEmpty () {
+	return props.isEmpty ();
+    }
+
+    public String getProperty (String name) {
+	if (System.currentTimeMillis () - lastcheck > cacheTime)
+	    checkFile ();
+	return props.getProperty (name.toLowerCase());
+    }
+
+    public String getProperty (String name, String defaultValue) {
+	if (System.currentTimeMillis () - lastcheck > cacheTime)
+	    checkFile ();
+	return props.getProperty (name.toLowerCase(), defaultValue);
+    }
+
+    public Enumeration keys () {
+	if (System.currentTimeMillis () - lastcheck > cacheTime)
+	    checkFile ();
+	return props.keys();
+    }
+
+    public Enumeration elements () {
+	if (System.currentTimeMillis () - lastcheck > cacheTime)
+	    checkFile ();
+	return props.elements();
+    }
+
+}
+
+
+
+
+