/*- * See the file LICENSE for redistribution information. * * Copyright (c) 1997-2006 *	Oracle Corporation.  All rights reserved. * * $Id: AccessExample.java,v 12.4 2006/08/24 14:45:51 bostic Exp $ */package collections.access;import java.io.File;import java.io.FileNotFoundException;import java.io.IOException;import java.io.InputStreamReader;import java.io.PrintStream;import java.util.Iterator;import java.util.Map;import java.util.SortedMap;import com.sleepycat.bind.ByteArrayBinding;import com.sleepycat.collections.StoredIterator;import com.sleepycat.collections.StoredSortedMap;import com.sleepycat.collections.TransactionRunner;import com.sleepycat.collections.TransactionWorker;import com.sleepycat.db.Database;import com.sleepycat.db.DatabaseConfig;import com.sleepycat.db.DatabaseException;import com.sleepycat.db.DatabaseType;import com.sleepycat.db.Environment;import com.sleepycat.db.EnvironmentConfig;/** *  AccesssExample mirrors the functionality of a class by the same name * used to demonstrate the com.sleepycat.je Java API. This version makes * use of the new com.sleepycat.collections.* collections style classes to make * life easier. * *@author     Gregory Burd *@created    October 22, 2002 */public class AccessExample         implements Runnable {    // Class Variables of AccessExample class    private static boolean create = true;    private static final int EXIT_SUCCESS = 0;    private static final int EXIT_FAILURE = 1;    public static void usage() {	System.out.println("usage: java " + AccessExample.class.getName() +            " [-r] [database]\n");	System.exit(EXIT_FAILURE);    }    /**     *  The main program for the AccessExample class     *     *@param  argv  The command line arguments     */    public static void main(String[] argv) {	boolean removeExistingDatabase = false;	String databaseName = "access.db";	for (int i = 0; i < argv.length; i++) {	    if (argv[i].equals("-r")) {		removeExistingDatabase = true;	    } else if (argv[i].equals("-?")) {		usage();	    } else if (argv[i].startsWith("-")) {		usage();	    } else {		if ((argv.length - i) != 1)		    usage();		databaseName = argv[i];		break;	    }	}        try {            EnvironmentConfig envConfig = new EnvironmentConfig();            envConfig.setTransactional(true);            envConfig.setInitializeCache(true);            envConfig.setInitializeLocking(true);            if (create) {                envConfig.setAllowCreate(true);            }            Environment env = new Environment(new File("."), envConfig);	    // Remove the previous database.	    if (removeExistingDatabase) {                env.removeDatabase(null, databaseName, null);            }            // create the app and run it            AccessExample app = new AccessExample(env, databaseName);            app.run();        } catch (DatabaseException e) {            e.printStackTrace();            System.exit(1);        } catch (FileNotFoundException e) {            e.printStackTrace();            System.exit(1);        } catch (Exception e) {            e.printStackTrace();            System.exit(1);        }        System.exit(0);    }    private Database db;    private SortedMap map;    private Environment env;    /**     *  Constructor for the AccessExample object     *     *@param  env            Description of the Parameter     *@exception  Exception  Description of the Exception     */    public AccessExample(Environment env, String databaseName)	throws Exception {        this.env = env;        //        // Lets mimic the db.AccessExample 100%        // and use plain old byte arrays to store the key and data strings.        //        ByteArrayBinding keyBinding = new ByteArrayBinding();        ByteArrayBinding dataBinding = new ByteArrayBinding();        //        // Open a data store.        //        DatabaseConfig dbConfig = new DatabaseConfig();        if (create) {            dbConfig.setAllowCreate(true);            dbConfig.setType(DatabaseType.BTREE);        }        this.db = env.openDatabase(null, databaseName, null, dbConfig);        //        // Now create a collection style map view of the data store        // so that it is easy to work with the data in the database.        //        this.map = new StoredSortedMap(db, keyBinding, dataBinding, true);    }    /**     *  Main processing method for the AccessExample object     */    public void run() {        //        // Insert records into a Stored Sorted Map DatabaseImpl, where        // the key is the user input and the data is the user input        // in reverse order.        //        final InputStreamReader reader = new InputStreamReader(System.in);        for (; ; ) {            final String line = askForLine(reader, System.out, "input> ");            if (line == null) {                break;            }            final String reversed =		(new StringBuffer(line)).reverse().toString();            log("adding: \"" +		line + "\" : \"" +		reversed + "\"");            // Do the work to add the key/data to the HashMap here.            TransactionRunner tr = new TransactionRunner(env);            try {                tr.run(		       new TransactionWorker() {			   public void doWork() {			       if (!map.containsKey(line.getBytes()))				   map.put(line.getBytes(),                                           reversed.getBytes());			       else				   System.out.println("Key " + line +						      " already exists.");			   }		       });            } catch (com.sleepycat.db.DatabaseException e) {                System.err.println("AccessExample: " + e.toString());                System.exit(1);            } catch (java.lang.Exception e) {                System.err.println("AccessExample: " + e.toString());                System.exit(1);            }        }        System.out.println("");        // Do the work to traverse and print the HashMap key/data        // pairs here get iterator over map entries.        Iterator iter = map.entrySet().iterator();        try {            System.out.println("Reading data");            while (iter.hasNext()) {                Map.Entry entry = (Map.Entry) iter.next();                log("found \"" +		    new String((byte[]) entry.getKey()) +		    "\" key with data \"" +		    new String((byte[]) entry.getValue()) + "\"");            }        } finally {            // Ensure that all database iterators are closed.  This is very            // important.            StoredIterator.close(iter);        }    }    /**     *  Prompts for a line, and keeps prompting until a non blank line is     *  returned. Returns null on error.     *     *@param  reader  stream from which to read user input     *@param  out     stream on which to prompt for user input     *@param  prompt  prompt to use to solicit input     *@return         the string supplied by the user     */    String askForLine(InputStreamReader reader, PrintStream out,                      String prompt) {        String result = "";        while (result != null && result.length() == 0) {            out.print(prompt);            out.flush();            result = getLine(reader);        }        return result;    }    /**     *  Read a single line. Gets the line attribute of the AccessExample object     *  Not terribly efficient, but does the job. Works for reading a line from     *  stdin or a file.     *     *@param  reader  stream from which to read the line     *@return         either a String or null on EOF, if EOF appears in the     *      middle of a line, returns that line, then null on next call.     */    String getLine(InputStreamReader reader) {        StringBuffer b = new StringBuffer();        int c;        try {            while ((c = reader.read()) != -1 && c != '\n') {                if (c != '\r') {                    b.append((char) c);                }            }        } catch (IOException ioe) {            c = -1;        }        if (c == -1 && b.length() == 0) {            return null;        } else {            return b.toString();        }    }    /**     *  A simple log method.     *     *@param  s  The string to be logged.     */    private void log(String s) {        System.out.println(s);        System.out.flush();    }}