yacy_search_server/source/de/anomic/server/serverObjects.java

// serverObjects.java 
// -----------------------
// (C) by Michael Peter Christen; mc@anomic.de
// first published on http://www.anomic.de
// Frankfurt, Germany, 2004
// last major change: 05.06.2004
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
//
// Using this software in any meaning (reading, learning, copying, compiling,
// running) means that you agree that the Author(s) is (are) not responsible
// for cost, loss of data or any harm that may be caused directly or indirectly
// by usage of this softare or this documentation. The usage of this software
// is on your own risk. The installation and usage (starting/running) of this
// software may allow other people or application to access your computer and
// any attached devices and is highly dependent on the configuration of the
// software which must be done by the user of the software; the author(s) is
// (are) also not responsible for proper configuration and usage of the
// software, even if provoked by documentation provided together with
// the software.
//
// Any changes to this file according to the GPL as documented in the file
// gpl.txt aside this file in the shipment you received can be done to the
// lines that follows this copyright notice here, but changes must not be
// done inside the copyright notive above. A re-distribution must contain
// the intact and unchanged copyright notice.
// Contributions and changes to the program code must be marked as such.

/*
  Why do we need this Class?
  The purpose of this class is to provide a hashtable object to the server
  and implementing interfaces. Values to and from cgi pages are encapsulated in
  this object. The server shall be executable in a Java 1.0 environment,
  so the following other options did not comply:

  Properties - setProperty would be needed, but only available in 1.2
  HashMap, TreeMap - only in 1.2
  Hashtable - available in 1.0, but 'put' does not accept null values

  So this class was created as a convenience.
  It will also contain special methods that read data from internet-resources
  in the background, while data can already be read out of the object.
  This shall speed up usage when a slow internet connection is used (dial-up)
*/

package de.anomic.server;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Map;
import java.util.Vector;

public final class serverObjects extends Hashtable implements Cloneable {

    public serverObjects() {
        super();
    }
    
    public serverObjects(int initialCapacity) {
        super(initialCapacity);
    }
    
    public serverObjects(Map input) {
	super(input);
    }

    // new put takes also null values
    public Object put(Object key, Object value) {
	if (key == null) {
	    // this does nothing
	    return null;
	} else if (value == null) {
	    // assigning the null value creates the same effect like removing the element
	    return super.remove(key);
	} else {
	    return super.put(key, value);
	}
    }

    // byte[] variant
    public byte[] put(String key, byte[] value) {
	return (byte[]) this.put((Object) key, (Object) value);
    }
    
    // string variant
    public String put(String key, String value) {
	return (String) this.put((Object) key, (Object) value);
    }

    // long variant
    public long put(String key, long value) {
	String result = this.put(key, "" + value);
	if (result == null) return 0; else try {
            return Long.parseLong(result);
        } catch (NumberFormatException e) {
            return 0;
        }
    }

    // inc variant: for counters
    public long inc(String key) {
	String c = (String) super.get(key);
	if (c == null) c = "0";
	long l = Long.parseLong(c) + 1;
	super.put(key, "" + l);
	return l;
    }

    // new get with default objects
    public Object get(Object key, Object dflt) {
	Object result = super.get(key);
	if (result == null) return dflt; else return result;
    }

    // string variant
    public String get(String key, String dflt) {
	return (String) this.get((Object) key, (Object) dflt);
    }

    // returns a set of all values where their key mappes the keyMapper
    public String[] getAll(String keyMapper) {
        // the keyMapper may contain regular expressions as defined in String.matches
        // this method is particulary useful when parsing the result of checkbox forms
        Vector v = new Vector();
	Enumeration e = keys();
	String key;
	while (e.hasMoreElements()) {
	    key = (String) e.nextElement();
            if (key.matches(keyMapper)) v.add(get(key));
	}
        // make a String[]
        String[] result = new String[v.size()];
        for (int i = 0; i < v.size(); i++) result[i] = (String) v.elementAt(i);
        return result;
    }

    // put all elements of another hastable into the own table
    public void putAll(serverObjects add) {
	Enumeration e = add.keys();
	Object k;
	while (e.hasMoreElements()) {
	    k = e.nextElement();
	    put(k, add.get(k));
	}
    }

    // convenience methods for storing and loading to a file system
    public void store(File f) throws IOException {
        BufferedOutputStream fos = null;
        try {
            fos = new BufferedOutputStream(new FileOutputStream(f));
            Enumeration e = keys();
            String key, value;
            while (e.hasMoreElements()) {
                key = (String) e.nextElement();
                value = ((String) get(key)).replaceAll("\n", "\\\\n");  
                fos.write((key + "=" + value + "\r\n").getBytes());
            }
        } finally {
            if (fos != null) {
                try {
                    fos.flush();
                    fos.close();
                } catch (Exception e){}
            }
        }
    }

    public Object clone() {
	return super.clone();
    }

}