ibatis 第一步

hibernate忘得也差不多了，先看看ibatis吧，算是一个最简单的入门,看着官方文档做了一个例子。

数据库配置与ibatis的总配置文件

jdbc.properties

driver=oracle.jdbc.driver.OracleDriver url=jdbc:oracle:thin:@localhost:1521:orcl username=scott password=tiger

configuration.xml

<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE configuration PUBLIC "-//ibatis.apache.org//DTD Config 3.0//EN" "http://ibatis.apache.org/dtd/ibatis-3-config.dtd"> <configuration> <properties resource="cn/enjoylife/config/jdbc.properties"/> <typeAliases> <typeAlias alias="Blog" type="cn.enjoylife.domain.Blog"/> </typeAliases> <environments default="development"> <environment id="development"> <transactionManager type="JDBC" /> <dataSource type="POOLED"> <property name="driver" value="${driver}" /> <property name="url" value="${url}" /> <property name="username" value="${username}" /> <property name="password" value="${password}" /> </dataSource> </environment> </environments> <mappers> <!-- xml配置文件 --> <mapper resource="cn/enjoylife/domain/Blog.xml"/> </mappers> </configuration>

sql配置文件与Mapper(使用注解的方式):

Blog.xml

<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper PUBLIC "-//ibatis.apache.org//DTD Mapper 3.0//EN" "http://ibatis.apache.org/dtd/ibatis-3-mapper.dtd"> <mapper namespace="cn.enjoylife.BlogMapper"> <select id="selectBlog" parameterType="int" resultType="Blog" > select id,title,content from Blog where id = #{id} </select> <insert id="insertBlog" parameterType="Blog" > insert into Blog(id,title,content) values(#{id},#{title},#{content}) </insert> <insert id="insertBlogBySequence" > insert into Blog(id,title,content) values(blogsequence.nextVal,#{title},#{content}) </insert> <update id="updateBlog" parameterType="Blog"> update Blog set title=#{title},content=#{content} where id=#{id} </update> <delete id="deleteBlog" parameterType="int"> delete from Blog where id=#{id} </delete> </mapper>

BlogMapper.java

package cn.enjoylife.mapper; import org.apache.ibatis.annotations.Select; import cn.enjoylife.domain.Blog; public interface BlogMapper { @Select("SELECT * FROM blog WHERE id=#{id}") Blog selectBlog(int id); }

对增删改查测试IbatisTest.java(Blog.java略)：

package junit.test; import java.io.Reader; import org.apache.ibatis.io.Resources; import org.apache.ibatis.session.SqlSession; import org.apache.ibatis.session.SqlSessionFactory; import org.apache.ibatis.session.SqlSessionFactoryBuilder; import org.junit.BeforeClass; import org.junit.Test; import cn.enjoylife.domain.Blog; import cn.enjoylife.mapper.BlogMapper; public class IbatisTest { private static SqlSessionFactory sqlSessionFactory; @BeforeClass public static void setUpBeforeClass() throws Exception { String resource = "cn/enjoylife/config/configuration.xml"; Reader reader = Resources.getResourceAsReader(resource); sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader); // 使用注解的方式需要对BlogMapper进行注册 // sqlSessionFactory.getConfiguration().addMapper(BlogMapper.class); } @Test public void testSqlSessionFactory() throws Exception { System.out.println(sqlSessionFactory); } @Test public void testSelect() { SqlSession session = sqlSessionFactory.openSession(); Blog blog = (Blog) session.selectOne( "cn.enjoylife.BlogMapper.selectBlog", 2); // HashMap // map=(HashMap)session.selectOne("cn.enjoylife.BlogMapper.selectBlog", // 1); // BlogMapper mapper=session.getMapper(BlogMapper.class); // Blog blog=mapper.selectBlog(2); System.out.println(blog.getTitle()); session.close(); } @Test public void testInsert() { SqlSession session = sqlSessionFactory.openSession(); try { Blog blog = new Blog(); blog.setTitle("oracle"); blog.setContent("使用序列！"); int n = session.insert( "cn.enjoylife.BlogMapper.insertBlogBySequence", blog); session.commit(); } catch (Exception e) { e.printStackTrace(); session.rollback(); } finally { session.close(); } } @Test public void testUpdate() { SqlSession session = sqlSessionFactory.openSession(); try { Blog blog = new Blog(); blog.setId(10); blog.setTitle("oracle"); blog.setContent("oracle"); int n = session.update("cn.enjoylife.BlogMapper.updateBlog", blog); session.commit(); } catch (Exception e) { e.printStackTrace(); session.rollback(); } finally { session.close(); } } @Test public void testDelete() { SqlSession session = sqlSessionFactory.openSession(); try { int n = session.delete("cn.enjoylife.BlogMapper.deleteBlog", 10); session.commit(); } catch (Exception e) { e.printStackTrace(); session.rollback(); } finally { session.close(); } } public static void main(String[] args) throws Exception { String resource = "cn/enjoylife/config/configuration.xml"; Reader reader = Resources.getResourceAsReader(resource); sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader); // //使用注解的方式需要对BlogMapper进行注册 // sqlSessionFactory.getConfiguration().addMapper(BlogMapper.class); SqlSession session = sqlSessionFactory.openSession(); Blog blog = (Blog) session.selectOne( "cn.enjoylife.BlogMapper.selectBlog", 15); // BlogMapper mapper=session.getMapper(BlogMapper.class); // Blog blog=mapper.selectBlog(15); System.out.println(blog.getTitle()); session.close(); } }

关于selectKey问题：

<insert id="insertBlogBySequence" > <selectKey resultType="int" keyProperty="id" > select blogsequence.nextVal from dual </selectKey> insert into Blog(id,title,content) values(#{id}#,#{title},#{content}) </insert>

总是报异常，按照文档所示也是这要配置，先休息，有空在看看

org.apache.ibatis.exceptions.IbatisException: ### Error updating database. Cause: org.apache.ibatis.type.TypeException: Error setting null parameter. Most JDBC drivers require that the JdbcType must be specified for all nullable parameters. Cause: java.sql.SQLException: 无效的列类型 ### The error may involve defaultParameterMap ### The error occurred while setting parameters ### Cause: org.apache.ibatis.type.TypeException: Error setting null parameter. Most JDBC drivers require that the JdbcType must be specified for all nullable parameters. Cause: java.sql.SQLException: 无效的列类型 at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:8) at org.apache.ibatis.session.defaults.DefaultSqlSession.update(DefaultSqlSession.java:100) at org.apache.ibatis.session.defaults.DefaultSqlSession.insert(DefaultSqlSession.java:87) at junit.test.IbatisTest.testInsert(IbatisTest.java:54) 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:44) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15) at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41) at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20) at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28) at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:73) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:46) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:180) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:41) at org.junit.runners.ParentRunner$1.evaluate(ParentRunner.java:173) at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28) at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31) at org.junit.runners.ParentRunner.run(ParentRunner.java:220) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:46) 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) Caused by: org.apache.ibatis.type.TypeException: Error setting null parameter. Most JDBC drivers require that the JdbcType must be specified for all nullable parameters. Cause: java.sql.SQLException: 无效的列类型 at org.apache.ibatis.type.BaseTypeHandler.setParameter(BaseTypeHandler.java:17) at org.apache.ibatis.executor.parameter.DefaultParameterHandler.setParameters(DefaultParameterHandler.java:73) at org.apache.ibatis.executor.statement.PreparedStatementHandler.parameterize(PreparedStatementHandler.java:61) at org.apache.ibatis.executor.statement.RoutingStatementHandler.parameterize(RoutingStatementHandler.java:43) at org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:56) at org.apache.ibatis.executor.SimpleExecutor.doUpdate(SimpleExecutor.java:28) at org.apache.ibatis.executor.BaseExecutor.update(BaseExecutor.java:72) at org.apache.ibatis.executor.CachingExecutor.update(CachingExecutor.java:43) at org.apache.ibatis.session.defaults.DefaultSqlSession.update(DefaultSqlSession.java:98) ... 26 more Caused by: java.sql.SQLException: 无效的列类型 at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:112) at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:146) at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:208) at oracle.jdbc.driver.OracleStatement.getInternalType(OracleStatement.java:3424) at oracle.jdbc.driver.OraclePreparedStatement.setNullCritical(OraclePreparedStatement.java:4197) at oracle.jdbc.driver.OraclePreparedStatement.setNull(OraclePreparedStatement.java:4186) at org.apache.ibatis.type.BaseTypeHandler.setParameter(BaseTypeHandler.java:15) ... 34 more

那如果想传递多个不相关的参数，该如何做呢？