📄 persistent storage-teststore.java
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/* License * * Copyright 1994-2004 Sun Microsystems, Inc. All Rights Reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * * Redistribution of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * * Redistribution in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * Neither the name of Sun Microsystems, Inc. or the names of contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * This software is provided "AS IS," without a warranty of any kind. ALL * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN") * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. * * You acknowledge that this software is not designed, licensed or intended * for use in the design, construction, operation or maintenance of any * nuclear facility. */import java.io.*;import javax.microedition.midlet.*;import javax.microedition.rms.*;public class TestStore extends MIDlet { static final String DBNAME = "mydata"; public TestStore() { RecordStore rs = null; // Data is persistent across MIDlet invocations. // So, first clear out the old record store... try { RecordStore.deleteRecordStore( DBNAME ); } catch( Exception e ){ // ignore any errors... } // Now create a new one and dump // each element out.... try { rs = RecordStore.openRecordStore( DBNAME, true ); byte[] data1 = "Here is the first record".getBytes(); byte[] data2 = "And here is the second".getBytes(); byte[] data3 = "And then the third".getBytes(); data3[0] = 0; data3[data3.length-1] = (byte) -1; rs.addRecord( data1, 0, data1.length ); rs.addRecord( data2, 0, data2.length ); rs.addRecord( data3, 0, data3.length ); dumpRecordStore( rs, System.out ); rs.closeRecordStore(); } catch( RecordStoreException e ){ System.out.println( e ); } notifyDestroyed(); } public void dumpRecordStore( RecordStore rs, PrintStream out ) { if( rs == null ) return; StringBuffer hexLine = new StringBuffer(); StringBuffer charLine = new StringBuffer(); try { int lastID = rs.getNextRecordID(); byte[] data = new byte[100]; int size; for( int i = 1; i < lastID; ++i ){ try { size = rs.getRecordSize( i ); if( size > data.length ){ data = new byte[ size * 2 ]; } out.println( "Record " + i + " of size " + size ); rs.getRecord( i, data, 0 ); dumpRecord( data, size, out, hexLine, charLine, 16 ); out.println( "" ); } catch( InvalidRecordIDException e ){ continue; } } } catch( RecordStoreException e ){ out.println( "Exception reading record store: " + e ); } } private void dumpRecord( byte[] data, int size, PrintStream out, StringBuffer hexLine, StringBuffer charLine, int maxLen ) { if( size == 0 ) return; hexLine.setLength( 0 ); charLine.setLength( 0 ); int count = 0; for( int i = 0; i < size; ++i ){ char b = (char) ( data[i] & 0xFF ); if( b < 0x10 ){ hexLine.append( '0' ); } hexLine.append( Integer.toHexString( b ) ); hexLine.append( ' ' ); if( ( b >= 32 && b <= 127 ) || Character.isDigit( b ) || Character.isLowerCase( b ) || Character.isUpperCase( b ) ){ charLine.append( (char) b ); } else { charLine.append( '.' ); } if( ++count >= maxLen || i == size-1 ){ while( count++ < maxLen ){ hexLine.append( " " ); } hexLine.append( ' ' ); hexLine.append( charLine.toString() ); out.println( hexLine.toString() ); hexLine.setLength( 0 ); charLine.setLength( 0 ); count = 0; } } } public void destroyApp( boolean unconditional ) { } public void startApp() { } public void pauseApp() { }}
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