/**
*
連接池類
*/
packagecom.junones.test;
importjava.sql.Connection;
importjava.sql.SQLException;
importjava.util.HashMap;
importjava.util.Map;
importjava.util.Map.Entry;
importcom.mysql.jdbc.jdbc2.optional.MysqlDataSource;
publicclass
MySQLPool {
privatestatic
volatile
MySQLPool pool;
privateMysqlDataSource
ds;
privateMap<Connection,
Boolean> map;
privateString
url = "jdbc:mysql://localhost:3306/test";
privateString
username = "root";
privateString
password = "root1234";
privateint
initPoolSize = 10;
privateint
maxPoolSize = 200;
privateint
waitTime = 100;
privateMySQLPool()
{
init();
}
publicstatic
MySQLPool getInstance() {
if(pool
== null)
{
synchronized(MySQLPool.class)
{
if(pool
== null)
{
pool
= newMySQLPool();
}
}
}
returnpool;
}
privatevoid
init() {
try{
ds
= newMysqlDataSource();
ds.setUrl(url);
ds.setUser(username);
ds.setPassword(password);
ds.setCacheCallableStmts(true);
ds.setConnectTimeout(1000);
ds.setLoginTimeout(2000);
ds.setUseUnicode(true);
ds.setEncoding("UTF-8");
ds.setZeroDateTimeBehavior("convertToNull");
ds.setMaxReconnects(5);
ds.setAutoReconnect(true);
map
= newHashMap<Connection,
Boolean>();
for(inti
= 0;
i < initPoolSize; i++) {
map.put(getNewConnection(),true);
}
}catch(Exception
e) {
e.printStackTrace();
}
}
publicConnection
getNewConnection() {
try{
returnds.getConnection();
}catch(SQLException
e) {
e.printStackTrace();
}
returnnull;
}
publicsynchronized
Connection getConnection() {
Connection
conn = null;
try{
for(Entry<Connection,
Boolean> entry : map.entrySet()) {
if(entry.getValue())
{
conn
= entry.getKey();
map.put(conn,false);
break;
}
}
if(conn
== null)
{
if(map.size()
< maxPoolSize) {
conn
= getNewConnection();
map.put(conn,false);
}else{
wait(waitTime);
conn
= getConnection();
}
}
}catch(Exception
e) {
e.printStackTrace();
}
returnconn;
}
publicvoid
releaseConnection(Connection conn) {
if(conn
== null)
{
return;
}
try{
if(map.containsKey(conn))
{
if(conn.isClosed())
{
map.remove(conn);
}else{
if(!conn.getAutoCommit())
{
conn.setAutoCommit(true);
}
map.put(conn,true);
}
}else{
conn.close();
}
}catch(SQLException
e) {
e.printStackTrace();
}
}
}
/**
*
測試類
*/
packagecom.junones.test;
importjava.sql.Connection;
importjava.sql.ResultSet;
importjava.sql.SQLException;
importjava.sql.Statement;
publicclass
TestMySQLPool {
privatestatic
volatile
int
a;
privatesynchronized
static
void
incr() {
a++;
}
publicstatic
void
main(String[] args) throwsInterruptedException
{
inttimes
= 10000;
longstart
= System.currentTimeMillis();
for(inti
= 0;
i < times; i++) {
newThread(newRunnable()
{
@Override
publicvoid
run() {
MySQLPool
pool = MySQLPool.getInstance();
Connection
conn = pool.getConnection();
Statement
stmt = null;
ResultSet
rs = null;
try{
stmt
= conn.createStatement();
rs
= stmt.executeQuery("select
id, name from t_test");
while(rs.next())
{
System.out.println(rs.getInt(1)
+ ",
"
+
rs.getString(2));
}
}catch(SQLException
e) {
e.printStackTrace();
}finally{
incr();
if(rs
!= null)
{
try{
rs.close();
}catch(SQLException
e) {
e.printStackTrace();
}
}
if(stmt
!= null)
{
try{
stmt.close();
}catch(SQLException
e) {
}
}
pool.releaseConnection(conn);
}
}
}).start();
}
while(true)
{
if(a
== times) {
System.out.println("finished,
time:"
+
(System.currentTimeMillis() - start));
break;
}
Thread.sleep(100);
}
}
}
測試結果：1萬個併發，5秒完成。
