source: main/trunk/greenstone2/common-src/src/jdbmedit/Txt2Jdb.java@ 21400

/**********************************************************************
 *
 * Txt2Jdb.java -- 
 * A component of the Greenstone digital library software
 * from the New Zealand Digital Library Project at the 
 * University of Waikato, New Zealand.
 *
 * Copyright (C) 1999  The New Zealand Digital Library Project
 * 
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 **********************************************************************/

import java.io.BufferedInputStream;
import java.io.InputStream;

import jdbm.RecordManager;
import jdbm.RecordManagerFactory;
import jdbm.helper.FastIterator;
import jdbm.htree.HTree;

import java.io.IOException;
import java.util.Properties;


public class Txt2Jdb
{
    static String TNAME = "greenstone";

    RecordManager  recman_;
    HTree          hashtable_;


    public Txt2Jdb(String db_filename, boolean append)
    throws IOException
    {
        // create or open a record manager
        Properties props = new Properties();
        recman_ = RecordManagerFactory.createRecordManager(db_filename, props);

        // create new table or (if append) load existing table
        long recid = recman_.getNamedObject(TNAME);
        if (append) {
        if (recid != 0) {
        System.out.println("Appending to existing database table '" + TNAME +"' ...");
        hashtable_ = HTree.load(recman_, recid);
        }
        else {
        System.out.println("No database table '" + TNAME +"' to append to.  Creating new one");
        hashtable_ = HTree.createInstance(recman_);
        recman_.setNamedObject(TNAME, hashtable_.getRecid());
        }
        } 
    else {
            System.out.println("Creating new database table '" + TNAME +"' ...");
            hashtable_ = HTree.createInstance(recman_);
            recman_.setNamedObject(TNAME, hashtable_.getRecid());
        }
    }


    // Helper function to fill in for C++ equivalent
    // Assumes InputStream is a file or standard-in  
    // (no some other form of IO mapped device)
    public boolean eof(InputStream is) 
    throws IOException
    {
    return (is.available() == 0);
    }

    public void txt2db()
        throws IOException
    {

    // Port of main txt2db code (originally written in C++)
    // Note: might not be most efficient way to do things in Java

    StringBuffer key;
    StringBuffer value;
    StringBuffer tmp;
    int num_dashes = 0;

    boolean delkey = false;

    BufferedInputStream bis = new BufferedInputStream(System.in);
    
    int c = bis.read();
    while (!eof(bis)) {
        num_dashes = 0;
        key = new StringBuffer();
        value = new StringBuffer();
        
        // Parse out 'key' from [key]\n
        
        // scan for first occurrence of [
        while (!eof(bis) && c != '[') {
        c = bis.read();
        }

        
        if (!eof(bis)) {
        c = bis.read(); // skip [
        }

        
        // now look for closing ], building up 'key' as we go
        while (!eof(bis) && c != ']') {
        key.append ((char)c);
        c = bis.read();
        }
        
        if (!eof(bis)) {
        // most likely an eol char, but if '-', then signifies record
        // is to be deleted, not added
        c = bis.read();
        if (c == '-') { 
            delkey = true;
        }
        else {
            delkey = false;
        }
        }

        while (!eof(bis) && (c == '\n' || c == '\r')) {
        c = bis.read();
        }
        
        // look for 70 dashes
        tmp = new StringBuffer();
        while (!eof(bis) && (num_dashes < 70)) {
        if (c == '\n') {
            tmp.append((char)c);
            num_dashes = 0; 
            
        } else if (c == '\r') { 
            // Here we are able to process both Windows-specific
            // text files (containing carriage-return, newline) and
            // Linux text files (containing only newline
            // characters) by ignoring the Windows' carriage-return
            // altogether so that we produce a uniform database
            // file from either system's type of text file.
            //
            // If we don't ignore the carriage return here, txt.gz
            // files produced on Windows cause a GS library running
            // on Linux to break.
            num_dashes = 0;
            
        } else if (c == '-') {
            tmp.append((char)c);
            ++num_dashes;
            
        } else {
            value.append(tmp);
            value.append((char)c);
            tmp = new StringBuffer();
            num_dashes = 0;
        }
        c = bis.read();
        }
        
        // if the key is not an empty string store this key-value pair
        if (key.length()>0) {
        String key_str = key.toString();

        if (delkey) {
            // delete the given key
            hashtable_.remove(key_str);
        }
        else {          
            // add/append
            String value_str = value.toString();
            hashtable_.put(key_str,value_str); 
            recman_.commit();
        }
        }
    }   

        recman_.close();
    }


    
    public static void print_usage()
    {
    System.err.println("Usage: java Txt2Jdb [-append] database-name");
    System.exit(-1);
    }

    
    public static void main(String[] args)
    {
    int argc = args.length;

    // sanity check
    if (argc != 1 && argc != 2) {
        print_usage();
    }
    
    String dbname;
    boolean append = false;
    boolean delkey = false;
    
    if (argc == 2) {
        dbname = args[1];
        if (args[0].equals("-append")) {
        append = true;
        } else {
        System.err.println(args[0] + " is not a valid option.");
        print_usage();
        }
    } else {
        dbname = args[0];
    }

    try {

            Txt2Jdb table = new Txt2Jdb(dbname,append);
            table.txt2db();
        } 
    catch (IOException e) {
            e.printStackTrace();
        }



    }

}