使用DBUtils小框架

浏览数：24 / 时间：2015年06月12日

DBUtils对sqlserver好像支持不怎么好，经常出现问题

比如

三月 14, 2015 10:19:32 上午 com.mchange.v2.log.MLog 
信息: MLog clients using java 1.4+ standard logging.
三月 14, 2015 10:19:32 上午 com.mchange.v2.c3p0.C3P0Registry 
信息: Initializing c3p0-0.9.5 [built 02-January-2015 13:25:04 -0500; debug? true; trace: 10]
三月 14, 2015 10:19:32 上午 com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource 
信息: Initializing c3p0 pool... com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 5, acquireRetryAttempts -> 30, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 0, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, contextClassLoaderSource -> caller, dataSourceName -> sqlserver, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> com.microsoft.sqlserver.jdbc.SQLServerDriver, extensions -> {}, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, forceUseNamedDriverClass -> false, identityToken -> 2vnjwi9864jlrl1j21iiv|7609e871, idleConnectionTestPeriod -> 0, initialPoolSize -> 10, jdbcUrl -> jdbc:sqlserver://localhost:1433;database=test, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 0, maxIdleTimeExcessConnections -> 0, maxPoolSize -> 20, maxStatements -> 0, maxStatementsPerConnection -> 0, minPoolSize -> 5, numHelperThreads -> 3, preferredTestQuery -> null, privilegeSpawnedThreads -> false, properties -> {user=******, password=******}, propertyCycle -> 0, statementCacheNumDeferredCloseThreads -> 0, testConnectionOnCheckin -> false, testConnectionOnCheckout -> false, unreturnedConnectionTimeout -> 0, userOverrides -> {}, usesTraditionalReflectiveProxies -> false ]
java.sql.SQLException: com.microsoft.sqlserver.jdbc.SQLServerException: ‘?‘ 附近有语法错误。 Query: insert into teacher values(?,?,?) Parameters: [c325abd1-4298-49bf-be9f-2e5b670b2e48, huahua, 1000]
	at org.apache.commons.dbutils.AbstractQueryRunner.rethrow(AbstractQueryRunner.java:392)
	at org.apache.commons.dbutils.QueryRunner.update(QueryRunner.java:491)
	at org.apache.commons.dbutils.QueryRunner.update(QueryRunner.java:457)
	at com.liujie.dao.TeacherDao.addTeacher(TeacherDao.java:22)
	at com.liujie.service.TeacherService.addTeacher(TeacherService.java:11)
	at com.liujie.test.TeacherTest.testTeacher(TeacherTest.java:35)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
	at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
	at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

幸亏这是开源框架，还可以修改底层代码，但改了万一mysql又不能用了怎么办？所以就不了了之，

最佳组合推荐：mysql+c3p0+dbutils

c3p0的配置有这些：

<c3p0-config>

<default-config>

<property name="autoCommitOnClose">false</property>

<!--c3p0将建一张名为Test的空表，并使用其自带的查询语句进行测试。如果定义了这个参数那么

属性preferredTestQuery将被忽略。你不能在这张Test表上进行任何操作，它将只供c3p0测试

使用。Default: null-->

<!--获取连接失败将会引起所有等待连接池来获取连接的线程抛出异常。但是数据源仍有效

保留，并在下次调用getConnection()的时候继续尝试获取连接。如果设为true，那么在尝试

获取连接失败后该数据源将申明已断开并永久关闭。Default: false-->

<property name="breakAfterAcquireFailure">false</property>

<!--当连接池用完时客户端调用getConnection()后等待获取新连接的时间，超时后将抛出

SQLException,如设为0则无限期等待。单位毫秒。Default: 0 -->

<!--通过实现ConnectionTester或QueryConnectionTester的类来测试连接。类名需制定全路径。

Default: com.mchange.v2.c3p0.impl.DefaultConnectionTester-->

<!--指定c3p0 libraries的路径，如果（通常都是这样）在本地即可获得那么无需设置，默认null即可

Default: null-->

<!--Strongly disrecommended. Setting this to true may lead to subtle and bizarre bugs.

（文档原文）作者强烈建议不使用的一个属性-->

<property name="forceIgnoreUnresolvedTransactions">false</property>

<!--JDBC的标准参数，用以控制数据源内加载的PreparedStatements数量。但由于预缓存的statements

属于单个connection而不是整个连接池。所以设置这个参数需要考虑到多方面的因素。

如果maxStatements与maxStatementsPerConnection均为0，则缓存被关闭。Default: 0-->

<!--c3p0是异步操作的，缓慢的JDBC操作通过帮助进程完成。扩展这些操作可以有效的提升性能

通过多线程实现多个操作同时被执行。Default: 3-->

<!--当用户调用getConnection()时使root用户成为去获取连接的用户。主要用于连接池连接非c3p0

的数据源时。Default: null-->

<property name="overrideDefaultPassword">password</property>

<!--定义所有连接测试都执行的测试语句。在使用连接测试的情况下这个一显著提高测试速度。注意：

测试的表必须在初始数据源的时候就存在。Default: null-->

<property name="preferredTestQuery">select id from test where id=1</property>

<!--因性能消耗大请只在需要的时候使用它。如果设为true那么在每个connection提交的

时候都将校验其有效性。建议使用idleConnectionTestPeriod或automaticTestTable

等方法来提升连接测试的性能。Default: false -->

<property name="testConnectionOnCheckout">false</property>

在Hibernate（spring管理）中的配置：

<property name="driverClass"><value>oracle.jdbc.driver.OracleDriver</value></property>

<property name="jdbcUrl"><value>jdbc:oracle:thin:@localhost:1521:Test</value></property>

</bean>

支持事务的JDBCUtils

 1 public class JDBCUtils {
 2     static ThreadLocal<Connection> tl = new ThreadLocal<Connection>();
 3     private static ComboPooledDataSource cpds = null;
 4     static {
 5         cpds = new ComboPooledDataSource("sqlserver");
 6     }
 7 
 8     public static DataSource getDataSource() {
 9         return cpds;
10     }
11 
12     public static Connection getConnection() throws SQLException {
13         Connection conn = tl.get();
14 
15         if (conn == null) {
16             conn = cpds.getConnection();
17             tl.set(conn);
18         }
19 
20         return conn;
21     }
22 
23     public static void startTransaction() throws SQLException {
24         Connection conn = tl.get();
25 
26         if (conn == null) {
27             conn = getConnection();
28             tl.set(conn);
29         }
30         conn.setAutoCommit(false);
31     }
32 
33     public static void rollback() throws SQLException {
34         Connection conn = tl.get();
35         if (conn != null) {
36             conn.rollback();
37         }
38     }
39 
40     public static void commit() throws SQLException {
41         Connection conn = tl.get();
42         if (conn != null) {
43             conn.commit();
44         }
45     }
46 
47     public static void release() throws SQLException {
48         Connection conn = tl.get();
49         if (conn != null) {
50             conn.close();
51             tl.remove();
52         }
53     }
54 
55 }