（笔记）Spring实战_征服数据库（3）_在Spring中使用JDBC

使用JDBC能够更好地对数据访问的性能进行调优。JDBC允许用户使用数据库的所有特性，而这是其他框架不鼓励甚至禁止的。

JDBC能够让我们在更低的层次上处理数据，能够访问和管理数据库中单独的列（细粒度的数据访问方式）。

Spring的JDBC框架承担了资源管理和异常处理的工作，从而简化了JDBC代码，让我们只需编写从数据库读写数据的必要代码。

使用SimpleJdbcTemplate访问数据

pom.xml

<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>3.2.17.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>3.2.17.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>3.2.17.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>3.2.17.RELEASE</version>
</dependency>
<dependency>
<groupId>com.oracle</groupId>
<artifactId>ojdbc6</artifactId>
<version>11.2.0.1.0</version>
</dependency>

DB

-- Create table
create table SPITTER
(
id       NUMBER,
username VARCHAR2(20) not null,
password VARCHAR2(20) not null,
fullname VARCHAR2(50) not null,
email    VARCHAR2(50) not null
)
tablespace SPRINGINACTION
pctfree 10
initrans 1
maxtrans 255
storage
(
initial 64K
minextents 1
maxextents unlimited
);
-- Create/Recreate primary, unique and foreign key constraints
alter table SPITTER
add constraint P_ID primary key (ID)
disable;

spring-spitter.xml

<bean id="jdbcTemplate" class="org.springframework.jdbc.core.simple.SimpleJdbcTemplate">
<constructor-arg ref="dataSource_JDBC" />
</bean>

<bean id="spitterDao" class="com.springinaction.spitter.JdbcSpitterDAO">
<property name="jdbcTemplate" ref="jdbcTemplate" />
</bean>

Spitter.java

package com.springinaction.spitter;

public class Spitter
{
private int id;

private String username;

private String password;

private String fullname;

private String email;

/**
* @return Returns the id.
*/
public int getId()
{
return id;
}

/**
* @param id
*            The id to set.
*/
public void setId(int id)
{
this.id = id;
}

/**
* @return Returns the username.
*/
public String getUsername()
{
return username;
}

/**
* @param username
*            The username to set.
*/
public void setUsername(String username)
{
this.username = username;
}

/**
* @return Returns the password.
*/
public String getPassword()
{
return password;
}

/**
* @param password
*            The password to set.
*/
public void setPassword(String password)
{
this.password = password;
}

/**
* @return Returns the fullname.
*/
public String getFullname()
{
return fullname;
}

/**
* @param fullname
*            The fullname to set.
*/
public void setFullname(String fullname)
{
this.fullname = fullname;
}

/**
* @return Returns the email.
*/
public String getEmail()
{
retur
11b40
n email;
}

/**
* @param email
*            The email to set.
*/
public void setEmail(String email)
{
this.email = email;
}

@Override
public String toString()
{
return "Spitter [id=" + id + ", username=" + username + ", password=" + password
+ ", fullname=" + fullname + ", email=" + email + "]";
}

}

SpitterDAO.java

package com.springinaction.spitter;

public interface SpitterDAO
{

public void addSpitter(Spitter spitter);

public Spitter getSpitterById(int id);
}

JdbcSpitterDAO.java

package com.springinaction.spitter;

import java.sql.ResultSet;
import java.sql.SQLException;

import org.springframework.jdbc.core.simple.ParameterizedRowMapper;
import org.springframework.jdbc.core.simple.SimpleJdbcTemplate;

public class JdbcSpitterDAO implements SpitterDAO
{

private SimpleJdbcTemplate jdbcTemplate;

public void setJdbcTemplate(SimpleJdbcTemplate jdbcTemplate)
{
this.jdbcTemplate = jdbcTemplate;
}

public void addSpitter(Spitter spitter)
{
jdbcTemplate.update(
"INSERT INTO SPITTER(ID,USERNAME,PASSWORD,FULLNAME,EMAIL) VALUES(?,?,?,?,?)",
spitter.getId(), spitter.getUsername(), spitter.getPassword(), spitter.getFullname(),
spitter.getEmail());
}

public Spitter getSpitterById(int id)
{
Spitter spitter = jdbcTemplate.queryForObject(
"SELECT ID,USERNAME,PASSWORD,FULLNAME,EMAIL FROM SPITTER WHERE ID=?",
new ParameterizedRowMapper<Spitter>()
{

public Spitter mapRow(ResultSet rs, int rowNum)
throws SQLException
{
Spitter spitter = new Spitter();
spitter.setId(rs.getInt(1));
spitter.setUsername(rs.getString(2));
spitter.setPassword(rs.getString(3));
spitter.setFullname(rs.getString(4));
spitter.setEmail(rs.getString(5));
return spitter;
}

}, id);
return spitter;
}

}

Test Demo

package com.springinaction.springtest;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.springinaction.spitter.JdbcSpitterDAO;
import com.springinaction.spitter.Spitter;

public class Demo
{

@Test
public void test1()
{
ApplicationContext ctx = new ClassPathXmlApplicationContext(
"com/springinaction/spitter/spring-spitter.xml");
JdbcSpitterDAO dao = (JdbcSpitterDAO)ctx.getBean("spitterDao");
Spitter spitter = new Spitter();
spitter.setId(1);
spitter.setUsername("Jagger");
spitter.setPassword("123456");
spitter.setFullname("Jagger S Y CHEN");
spitter.setEmail("43970615@XX.com");
dao.addSpitter(spitter);
}

@Test
public void test2()
{
ApplicationContext ctx = new ClassPathXmlApplicationContext(
"com/springinaction/spitter/spring-spitter.xml");
JdbcSpitterDAO dao = (JdbcSpitterDAO)ctx.getBean("spitterDao");
Spitter spitter = dao.getSpitterById(1);
System.out.println(spitter);
}

}

使用命名参数

使用命名参数查询，绑定值的顺序就不重要了，我们可以按照名字来绑定值。如果查询语句发生了变化导致参数的顺序与之前不一致，我们不需要修改绑定的代码。

public void addSpitterByNamedParameter(Spitter spitter)
{
Map<String, Object> params = new HashMap<String, Object>();
params.put("id", spitter.getId());
params.put("username", spitter.getUsername());
params.put("password", spitter.getPassword());
params.put("fullname", spitter.getFullname());
params.put("email", spitter.getEmail());
jdbcTemplate.update(
"INSERT INTO SPITTER(ID,USERNAME,PASSWORD,FULLNAME,EMAIL) VALUES(:id,:username,:password,:fullname,:email)",
params);
}

使用Spring的JDBC DAO支持类

spring-spitter.xml

<bean id="spitterSupportDao" class="com.springinaction.spitter.JdbcSpitterSupportDAO">
<property name="dataSource" ref="dataSource_JDBC" />
</bean>

JdbcSpitterSupportDAO.java

package com.springinaction.spitter;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.Map;

import org.springframework.jdbc.core.simple.ParameterizedRowMapper;
import org.springframework.jdbc.core.simple.SimpleJdbcDaoSupport;

public class JdbcSpitterSupportDAO extends SimpleJdbcDaoSupport implements SpitterDAO
{

public void addSpitter(Spitter spitter)
{
getJdbcTemplate().update(
"INSERT INTO SPITTER(ID,USERNAME,PASSWORD,FULLNAME,EMAIL) VALUES(?,?,?,?,?)",
spitter.getId(), spitter.getUsername(), spitter.getPassword(), spitter.getFullname(),
spitter.getEmail());
}

public Spitter getSpitterById(int id)
{
Spitter spitter = getJdbcTemplate().queryForObject(
"SELECT ID,USERNAME,PASSWORD,FULLNAME,EMAIL FROM SPITTER WHERE ID=?",
new ParameterizedRowMapper<Spitter>()
{

public Spitter mapRow(ResultSet rs, int rowNum)
throws SQLException
{
Spitter spitter = new Spitter();
spitter.setId(rs.getInt(1));
spitter.setUsername(rs.getString(2));
spitter.setPassword(rs.getString(3));
spitter.setFullname(rs.getString(4));
spitter.setEmail(rs.getString(5));
return spitter;
}

}, id);
return spitter;
}

public void addSpitterByNamedParameter(Spitter spitter)
{
Map<String, Object> params = new HashMap<String, Object>();
params.put("id", spitter.getId());
params.put("username", spitter.getUsername());
params.put("password", spitter.getPassword());
params.put("fullname", spitter.getFullname());
params.put("email", spitter.getEmail());
getJdbcTemplate().update(
"INSERT INTO SPITTER(ID,USERNAME,PASSWORD,FULLNAME,EMAIL) VALUES(:id,:username,:password,:fullname,:email)",
params);
}

}

执行addSpitterByNamedParameter()方法会抛出如下异常：

org.springframework.jdbc.UncategorizedSQLException: PreparedStatementCallback; uncategorized SQLException for SQL [INSERT INTO SPITTER(ID,USERNAME,PASSWORD,FULLNAME,EMAIL) VALUES(:id,:username,:password,:fullname,:email)]; SQL state [99999]; error code [17004]; 无效的列类型; nested exception is java.sql.SQLException: 无效的列类型
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:83)
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:80)
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:80)
at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:605)
at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:818)
at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:874)
at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:882)
at com.springinaction.spitter.JdbcSpitterSupportDAO.addSpitterByNamedParameter(JdbcSpitterSupportDAO.java:55)
at com.springinaction.springtest.Demo5.test6(Demo5.java:93)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)
Caused by: java.sql.SQLException: 无效的列类型
at oracle.jdbc.driver.OraclePreparedStatement.setObjectCritical(OraclePreparedStatement.java:8516)
at oracle.jdbc.driver.OraclePreparedStatement.setObjectInternal(OraclePreparedStatement.java:8034)
at oracle.jdbc.driver.OraclePreparedStatement.setObjectInternal(OraclePreparedStatement.java:8767)
at oracle.jdbc.driver.OraclePreparedStatement.setObject(OraclePreparedStatement.java:8748)
at oracle.jdbc.driver.OraclePreparedStatementWrapper.setObject(OraclePreparedStatementWrapper.java:230)
at org.springframework.jdbc.core.StatementCreatorUtils.setValue(StatementCreatorUtils.java:402)
at org.springframework.jdbc.core.StatementCreatorUtils.setParameterValueInternal(StatementCreatorUtils.java:234)
at org.springframework.jdbc.core.StatementCreatorUtils.setParameterValue(StatementCreatorUtils.java:165)
at org.springframework.jdbc.core.ArgumentPreparedStatementSetter.doSetValue(ArgumentPreparedStatementSetter.java:65)
at org.springframework.jdbc.core.ArgumentPreparedStatementSetter.setValues(ArgumentPreparedStatementSetter.java:46)
at org.springframework.jdbc.core.JdbcTemplate$2.doInPreparedStatement(JdbcTemplate.java:822)
at org.springframework.jdbc.core.JdbcTemplate$2.doInPreparedStatement(JdbcTemplate.java:818)
at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:589)
... 28 more