Sometimes you find a condition where your database connection (MySQL) is time out because of your queries are spending too much time. This is a hint on how you increase your MySQL time out configuration.
First you query your default connection timeout.
SHOW VARIABLES LIKE 'connect_timeout';
As you can see below, i have approximately 10 seconds before my mysql connection time out.
Next is updated it to 60 seconds.
SET GLOBAL connect_timeout=60;
Simple isn’t it. 😉
Well, it’s actually very simple, first of all you need to download libraries (mp3spi1.9.4.jar, jl1.0.jar and tritonus_share.jar) from Tritonus and from JLayer.
Here is how i code it,
package com.edw.mp3.main;
import java.io.File;
import java.io.IOException;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.LineUnavailableException;
import javax.sound.sampled.SourceDataLine;
import org.apache.log4j.Logger;
public class Main extends Thread {
private String filename;
private static Logger logger = Logger.getLogger(Main.class);
public Main(String filename) {
super();
this.filename = filename;
}
@Override
public void run() {
try {
File file = new File(filename);
AudioInputStream in = AudioSystem.getAudioInputStream(file);
AudioInputStream din = null;
AudioFormat baseFormat = in.getFormat();
AudioFormat decodedFormat = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED,
baseFormat.getSampleRate(),
16,
baseFormat.getChannels(),
baseFormat.getChannels() * 2,
baseFormat.getSampleRate(),
false);
din = AudioSystem.getAudioInputStream(decodedFormat, in);
// play it...
rawplay(decodedFormat, din);
in.close();
} catch (Exception e) {
logger.error(e.getMessage(),e);
} finally{
logger.debug("finish playing "+filename);
}
}
private synchronized void rawplay(AudioFormat targetFormat, AudioInputStream din) throws IOException, LineUnavailableException {
byte[] data = new byte[4096];
SourceDataLine line = getLine(targetFormat);
if (line != null) {
// Start
line.start();
int nBytesRead = 0, nBytesWritten = 0;
while (nBytesRead != -1) {
nBytesRead = din.read(data, 0, data.length);
if (nBytesRead != -1) {
nBytesWritten = line.write(data, 0, nBytesRead);
}
}
// Stop
line.drain();
line.stop();
line.close();
din.close();
}
}
private synchronized SourceDataLine getLine(AudioFormat audioFormat) throws LineUnavailableException {
SourceDataLine res = null;
DataLine.Info info =
new DataLine.Info(SourceDataLine.class, audioFormat);
res = (SourceDataLine) AudioSystem.getLine(info);
res.open(audioFormat);
return res;
}
public static void main(String[] args) {
// my relative path file name
String song = "Bondan ft. Fade2Black-Ya Sudahlah.mp3";
logger.debug("start playing "+song);
Main mp3Sound = new Main(song);
mp3Sound.start();
}
}
And my Netbeans’ project structure
Actually i code it a long time ago, Thank God it’s still works. If you have any suggestion, feel free to comment it.
Cheers.. (B)
Well, it’s actually quite easy to create a simple calendar or datepicker using jquery. But first you need to download jQuery and jQuery UI libs. This is how you do it,
<html>
<head>
<title>JQuery Test</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<link href="datePicker.css" type="text/css" rel="stylesheet" />
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="jquery-datepicker.js"></script>
<script type="text/javascript">
$(function()
{
$('#date-pick').datepicker({
showOn: "button",
dateFormat: "dd/mm/yy",
disabled: true,
buttonImage: "calendar.png",
buttonImageOnly: true
});
});
</script>
</head>
<body>
Enter your birthdate :
<input name="date1" type="text" id="date-pick" size="10" maxlength="10" />
</body>
</html>
It will look like this,
For the live example, you can see here. Cheers (B)
Recently i’m developing a simple client server application, using serialized java objects as parameter. To increase performance, im trying to compress my java object. Here’s how i do it.
a simple serialized java bean
package com.edw.bean;
import java.io.Serializable;
import java.math.BigDecimal;
public class TestBean implements Serializable {
private BigDecimal id;
private String value;
public BigDecimal getId() {
return id;
}
public void setId(BigDecimal id) {
this.id = id;
}
public String getValue() {
return value;
}
public void setValue(String value) {
this.value = value;
}
}
and a class to compress my object
package com.edw.main;
import com.edw.bean.TestBean;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.math.BigDecimal;
import java.util.zip.Deflater;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
import org.apache.log4j.Logger;
public class Main {
private final static Logger logger = Logger.getLogger(Main.class);
public Main() {
}
private void startApp() throws Exception {
// create a very big bean
TestBean tb = new TestBean();
tb.setId(new BigDecimal(Double.MAX_VALUE));
String bigString = "";
for (int i = 0; i < 5000; i++) {
bigString += " test " + i;
}
tb.setValue(bigString);
// write it to file to see this object's size
ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream(new File("test.size"), false));
oos.writeObject(tb);
oos.flush();
oos.close();
// get the serialized object
ObjectInputStream ois = new ObjectInputStream(new FileInputStream(new File("test.size")));
Object regularObject = ois.readObject();
logger.debug(((TestBean) regularObject).getId());
// write compressed object to file to see this object's size
FileOutputStream fos = new FileOutputStream(new File("testCompressed.size"), false);
GZIPOutputStream gzipos = new GZIPOutputStream(fos) {
{
def.setLevel(Deflater.BEST_COMPRESSION);
}
};
ObjectOutputStream oosCompressed = new ObjectOutputStream(gzipos);
oosCompressed.writeObject(tb);
oosCompressed.flush();
oosCompressed.close();
// get the serialized object
FileInputStream fis = new FileInputStream(new File("testCompressed.size"));
GZIPInputStream gzipis = new GZIPInputStream(fis);
ObjectInputStream oisCompressed = new ObjectInputStream(gzipis);
Object compressedObject = oisCompressed.readObject();
logger.debug(((TestBean) compressedObject).getId());
}
public static void main(String[] args) throws Exception {
Main main = new Main();
main.startApp();
}
}
it can compress up to 75% of size,
Thank you and have a good time coding. (*)
Some values in a database are know to change slower than others. To improve performance, many developers like to cache often-used data to avoid making unnecessary trips back to the database. iBATIS provides its own caching system, that you configure through a <cacheModel> element.
The results from a query Mapped Statement can be cached simply by specifying the cacheModel parameter. A cache model is a configured cache that is defined within your DataMapper configuration file. IBATIS cache focuses on caching results within the persistence layer. As such, it is independent of the service or presentation layers, and is not based on object identity.
In this simple example, i’m using OSCache. OSCache is a robust caching framework that is able to perform many of the same type of caching strategies that iBATIS provides in its other cache models. When using the OSCACHE model, you create a dependency on the OSCache JARs. You will need to include the OSCache JAR in your project when you use this setting. This cache is configured in the same manner as a standard OSCache install. This means that you will need to have an oscache.properties file available on the root of your classpath for OSCache to read.
Okay, here’s my code,
a simple “test” database, and a “contoh” table
CREATE DATABASE 'test'
USE 'test'
CREATE TABLE `contoh` (
`nama` varchar(30) NOT NULL DEFAULT '',
`alamat` varchar(100) DEFAULT NULL,
PRIMARY KEY (`nama`)
)
insert into contoh (nama, alamat) values ('edwin', 'jakarta');
insert into contoh (nama, alamat) values ('kamplenk', 'ciledug');
insert into contoh (nama, alamat) values ('nugie', 'pamulang');
insert into contoh (nama, alamat) values ('samsu', 'dago');
insert into contoh (nama, alamat) values ('tebek', 'jayapura');
a contoh POJO
package com.edw.bean;
/**
*
* @author edw
*/
public class Contoh {
private String nama;
private String alamat;
// other setter and getter
}
and my sqlmapconfig.xml as my ibatis xml configuration
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sqlMapConfig
PUBLIC "-//ibatis.apache.org//DTD SQL Map Config 2.0//EN"
"http://ibatis.apache.org/dtd/sql-map-config-2.dtd">
<sqlMapConfig>
<settings
useStatementNamespaces="true"
lazyLoadingEnabled="true"
enhancementEnabled="true"
maxSessions="20"
/>
<transactionManager type="JDBC" commitRequired="false">
<dataSource type="SIMPLE">
<property name="SetAutoCommitAllowed" value="false"/>
<property name="DefaultAutoCommit" value="false"/>
<property name="JDBC.Driver" value="com.mysql.jdbc.Driver"/>
<property name="JDBC.ConnectionURL" value="jdbc:mysql://localhost/test"/>
<property name="JDBC.Username" value="root"/>
<property name="JDBC.Password" value="xxx"/>
</dataSource>
</transactionManager>
<sqlMap resource="com/edw/sqlmap/contoh.xml"/>
</sqlMapConfig>
and my xml query, at line 5 to 9 is my OSCache caching, and at line 21 is cacheModel implementation on query “selectAllContoh”. It means that i’m storing “selectAllContoh” resultSet on a cache, so the next time query “selectAllContoh” is called, iBatis will get resultSet from my cache instead of hitting my database.
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE sqlMap PUBLIC "-//ibatis.apache.org//DTD SQL Map 2.0//EN" "http://ibatis.apache.org/dtd/sql-map-2.dtd" >
<sqlMap namespace="contoh" >
<cacheModel id="contohCache" type="OSCACHE">
<flushInterval hours="24"/>
<flushOnExecute statement="contoh.insertContoh"/>
<property name="reference-type" value="SOFT"/>
</cacheModel>
<resultMap id="result" class="com.edw.bean.Contoh">
<result property="nama" column="NAMA" columnIndex="1"/>
<result property="alamat" column="ALAMAT" columnIndex="2"/>
</resultMap>
<insert id="insertContoh" parameterClass="com.edw.bean.Contoh" >
insert into contoh (nama, alamat)
values (#nama:VARCHAR#, #alamat:VARCHAR#)
</insert>
<select id="selectAllContoh" resultMap="result" cacheModel="contohCache">
select nama, alamat
from contoh
</select>
</sqlMap>
a class to load my ibatis xml configuration
package com.edw.config;
import com.ibatis.common.resources.Resources;
import com.ibatis.sqlmap.client.SqlMapClient;
import com.ibatis.sqlmap.client.SqlMapClientBuilder;
import java.io.Reader;
/**
*
* @author edw
*/
public class SqlMapConfig {
protected static final SqlMapClient sqlMap;
static {
try {
Reader reader = Resources.getResourceAsReader("com/edw/sqlmap/sqlmapconfig.xml");
sqlMap = SqlMapClientBuilder.buildSqlMapClient(reader);
} catch (Exception e){
throw new RuntimeException("Fatal Error. Cause: " + e, e);
}
}
public static SqlMapClient getSqlMap() {
return sqlMap;
}
}
and my log4j configuration, i named it log4j.properties
# Global logging configuration
log4j.rootLogger=DEBUG,stdout
# Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d [%c{1}] %-5p %c:%L - %m%n
and my oscache.properties
cache.capacity=1000
i create a simple JUnit class to test my class
package com.edw.test;
import com.edw.bean.Contoh;
import com.edw.config.SqlMapConfig;
import java.util.List;
import org.apache.log4j.Logger;
import org.junit.Test;
import static org.junit.Assert.*;
/**
*
* @author edw
*/
public class TestIbatisCaching {
@Test
public void testIbatisCaching() {
Logger logger = Logger.getLogger(this.getClass());
try {
// repeated queries
for (int i = 0; i < 5; i++) {
List<Contoh> contohs = SqlMapConfig.getSqlMap().queryForList("contoh.selectAllContoh");
// check if it's null
assertNotNull(contohs);
//sleep
Object o = new Object();
synchronized(o){
o.wait(2000);
}
for (Contoh contoh : contohs) {
logger.debug(contoh.getNama());
}
logger.debug("================================");
}
} catch (Exception ex) {
logger.error(ex);
}
}
}
this is what happen on my console,
on line 24-25 shows how OSCache creating a cache from a query “contoh.selectAllContoh”,
and on line 37-38 shows how query “contoh.selectAllContoh” hitting Ibatis’ cache instead of the database.
2010-10-09 18:49:24,961 [Config] DEBUG com.opensymphony.oscache.base.Config:61 - OSCache: Config called
2010-10-09 18:49:24,968 [Config] INFO com.opensymphony.oscache.base.Config:147 - OSCache: Properties read {cache.capacity=1000}
2010-10-09 18:49:24,969 [AbstractCacheAdministrator] DEBUG com.opensymphony.oscache.base.AbstractCacheAdministrator:160 - Constructed AbstractCacheAdministrator()
2010-10-09 18:49:24,993 [GeneralCacheAdministrator] INFO com.opensymphony.oscache.general.GeneralCacheAdministrator:98 - Constructed GeneralCacheAdministrator()
2010-10-09 18:49:24,993 [GeneralCacheAdministrator] INFO com.opensymphony.oscache.general.GeneralCacheAdministrator:301 - Creating new cache
2010-10-09 18:49:25,028 [AbstractConcurrentReadCache] DEBUG com.opensymphony.oscache.base.algorithm.AbstractConcurrentReadCache:694 - get called (key=1542486422|5257123254|contoh.selectAllContoh|1339823102| select nama, alamat from contoh |executeQueryForList|0|-999999)
2010-10-09 18:49:25,028 [AbstractConcurrentReadCache] DEBUG com.opensymphony.oscache.base.algorithm.AbstractConcurrentReadCache:1061 - persistRetrieve called (key=1542486422|5257123254|contoh.selectAllContoh|1339823102| select nama, alamat from contoh |executeQueryForList|0|-999999)
2010-10-09 18:49:25,099 [Cache] DEBUG com.opensymphony.oscache.base.Cache:697 - No cache entry exists for key='1542486422|5257123254|contoh.selectAllContoh|1339823102| select nama, alamat from contoh |executeQueryForList|0|-999999', creating
2010-10-09 18:49:25,106 [CacheModel] DEBUG com.ibatis.sqlmap.engine.cache.CacheModel:27 - Cache 'contoh.contohCache': cache miss
2010-10-09 18:49:25,331 [SimpleDataSource] DEBUG com.ibatis.common.jdbc.SimpleDataSource:27 - Created connection 5230193.
2010-10-09 18:49:25,334 [Connection] DEBUG java.sql.Connection:27 - {conn-100000} Connection
2010-10-09 18:49:25,336 [Connection] DEBUG java.sql.Connection:27 - {conn-100000} Preparing Statement: select nama, alamat from contoh
2010-10-09 18:49:25,381 [PreparedStatement] DEBUG java.sql.PreparedStatement:27 - {pstm-100001} Executing Statement: select nama, alamat from contoh
2010-10-09 18:49:25,405 [PreparedStatement] DEBUG java.sql.PreparedStatement:27 - {pstm-100001} Parameters: []
2010-10-09 18:49:25,406 [PreparedStatement] DEBUG java.sql.PreparedStatement:27 - {pstm-100001} Types: []
2010-10-09 18:49:25,411 [ResultSet] DEBUG java.sql.ResultSet:27 - {rset-100002} ResultSet
2010-10-09 18:49:25,429 [ResultSet] DEBUG java.sql.ResultSet:27 - {rset-100002} Header: [NAMA, ALAMAT]
2010-10-09 18:49:25,429 [ResultSet] DEBUG java.sql.ResultSet:27 - {rset-100002} Result: [edwin, singapore]
2010-10-09 18:49:25,430 [ResultSet] DEBUG java.sql.ResultSet:27 - {rset-100002} Result: [kamplenk, ciledug]
2010-10-09 18:49:25,430 [ResultSet] DEBUG java.sql.ResultSet:27 - {rset-100002} Result: [nugie, pamulang]
2010-10-09 18:49:25,511 [ResultSet] DEBUG java.sql.ResultSet:27 - {rset-100002} Result: [samsu, dago]
2010-10-09 18:49:25,513 [ResultSet] DEBUG java.sql.ResultSet:27 - {rset-100002} Result: [tebek, jayapura]
2010-10-09 18:49:25,514 [AbstractConcurrentReadCache] DEBUG com.opensymphony.oscache.base.algorithm.AbstractConcurrentReadCache:694 - get called (key=1542486422|5257123254|contoh.selectAllContoh|1339823102| select nama, alamat from contoh |executeQueryForList|0|-999999)
2010-10-09 18:49:25,515 [AbstractConcurrentReadCache] DEBUG com.opensymphony.oscache.base.algorithm.AbstractConcurrentReadCache:1061 - persistRetrieve called (key=1542486422|5257123254|contoh.selectAllContoh|1339823102| select nama, alamat from contoh |executeQueryForList|0|-999999)
2010-10-09 18:49:25,519 [Cache] DEBUG com.opensymphony.oscache.base.Cache:697 - No cache entry exists for key='1542486422|5257123254|contoh.selectAllContoh|1339823102| select nama, alamat from contoh |executeQueryForList|0|-999999', creating
2010-10-09 18:49:25,520 [AbstractConcurrentReadCache] DEBUG com.opensymphony.oscache.base.algorithm.AbstractConcurrentReadCache:1108 - persistStore called (key=1542486422|5257123254|contoh.selectAllContoh|1339823102| select nama, alamat from contoh |executeQueryForList|0|-999999)
2010-10-09 18:49:25,521 [AbstractConcurrentReadCache] DEBUG com.opensymphony.oscache.base.algorithm.AbstractConcurrentReadCache:1087 - persistRetrieveGroup called (groupName=contoh.contohCache)
2010-10-09 18:49:25,521 [AbstractConcurrentReadCache] DEBUG com.opensymphony.oscache.base.algorithm.AbstractConcurrentReadCache:1127 - persistStoreGroup called (groupName=contoh.contohCache)
2010-10-09 18:49:25,523 [CacheModel] DEBUG com.ibatis.sqlmap.engine.cache.CacheModel:27 - Cache 'contoh.contohCache': stored object '[com.edw.bean.Contoh@12bb7e0, com.edw.bean.Contoh@134f69a, com.edw.bean.Contoh@2a15cd, com.edw.bean.Contoh@fd68b1, com.edw.bean.Contoh@e45076]'
2010-10-09 18:49:25,525 [SimpleDataSource] DEBUG com.ibatis.common.jdbc.SimpleDataSource:27 - Returned connection 5230193 to pool.
2010-10-09 18:49:27,526 [TestIbatisCaching] DEBUG com.edw.test.TestIbatisCaching:34 - edwin
2010-10-09 18:49:27,526 [TestIbatisCaching] DEBUG com.edw.test.TestIbatisCaching:34 - kamplenk
2010-10-09 18:49:27,526 [TestIbatisCaching] DEBUG com.edw.test.TestIbatisCaching:34 - nugie
2010-10-09 18:49:27,526 [TestIbatisCaching] DEBUG com.edw.test.TestIbatisCaching:34 - samsu
2010-10-09 18:49:27,526 [TestIbatisCaching] DEBUG com.edw.test.TestIbatisCaching:34 - tebek
2010-10-09 18:49:27,526 [TestIbatisCaching] DEBUG com.edw.test.TestIbatisCaching:37 - ================================
2010-10-09 18:49:27,536 [AbstractConcurrentReadCache] DEBUG com.opensymphony.oscache.base.algorithm.AbstractConcurrentReadCache:694 - get called (key=1542486422|5257123254|contoh.selectAllContoh|1339823102| select nama, alamat from contoh |executeQueryForList|0|-999999)
2010-10-09 18:49:27,536 [CacheModel] DEBUG com.ibatis.sqlmap.engine.cache.CacheModel:27 - Cache 'contoh.contohCache': retrieved object '[com.edw.bean.Contoh@12bb7e0, com.edw.bean.Contoh@134f69a, com.edw.bean.Contoh@2a15cd, com.edw.bean.Contoh@fd68b1, com.edw.bean.Contoh@e45076]'
2010-10-09 18:49:29,536 [TestIbatisCaching] DEBUG com.edw.test.TestIbatisCaching:34 - edwin
2010-10-09 18:49:29,536 [TestIbatisCaching] DEBUG com.edw.test.TestIbatisCaching:34 - kamplenk
2010-10-09 18:49:29,536 [TestIbatisCaching] DEBUG com.edw.test.TestIbatisCaching:34 - nugie
2010-10-09 18:49:29,536 [TestIbatisCaching] DEBUG com.edw.test.TestIbatisCaching:34 - samsu
2010-10-09 18:49:29,536 [TestIbatisCaching] DEBUG com.edw.test.TestIbatisCaching:34 - tebek
2010-10-09 18:49:29,536 [TestIbatisCaching] DEBUG com.edw.test.TestIbatisCaching:37 - ================================
this is my Netbeans project structure
Well, i guess it can help others. Thank you and see you again. (H)