（四）Spring 对DAO 的支持
第一节：Spring 对JDBC 的支持
1，配置数据源dbcp；
2，使用JdbcTemplate；
3，JdbcDaoSupport 的使用；
4，NamedParameterJdbcTemplate 的使用；支持命名参数变量；
org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate
1，使用JdbcTemplate；
T.java:
package com.wishwzp.test; import java.util.List; import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext; import com.wishwzp.model.Student;
import com.wishwzp.service.StudentService; public class T { private ApplicationContext ac; @Before
public void setUp() throws Exception {
ac=new ClassPathXmlApplicationContext("beans.xml");
} //添加
@Test
public void addStudent() {
StudentService studentService=(StudentService)ac.getBean("studentService");
int addNums=studentService.addStudent(new Student("王五", 1));
if(addNums==1){
System.out.println("添加成功");
}
} //更新
@Test
public void updateStudent() {
StudentService studentService=(StudentService)ac.getBean("studentService");
int updateNums=studentService.updateStudent(new Student(8,"王五2", 2));
if(updateNums==1){
System.out.println("更新成功");
}
} //删除
@Test
public void deleteStudent() {
StudentService studentService=(StudentService)ac.getBean("studentService");
int deleteNums=studentService.deleteStudent(8);
if(deleteNums==1){
System.out.println("删除成功");
}
} //查找
@Test
public void findStudents() {
StudentService studentService=(StudentService)ac.getBean("studentService");
List<Student> studentList=studentService.findStudents();
for(Student student:studentList){
System.out.println(student);
}
} }
beans.xml:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd"> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<property name="driverClassName" value="${jdbc.driverClassName}"/>
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
</bean> <context:property-placeholder location="jdbc.properties"/> <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource"></property>
</bean> <bean id="studentDao" class="com.wishwzp.dao.impl.StudentDaoImpl">
<property name="jdbcTemplate" ref="jdbcTemplate"></property>
</bean> <bean id="studentService" class="com.wishwzp.service.impl.StudentServiceImpl">
<property name="studentDao" ref="studentDao"></property>
</bean> </beans>
jdbc.properties:
jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/db_spring?characterEncoding=utf-8
jdbc.username=root
jdbc.password=root
StudentServiceImpl.java:
package com.wishwzp.service.impl; import java.util.List; import com.wishwzp.dao.StudentDao;
import com.wishwzp.model.Student;
import com.wishwzp.service.StudentService; public class StudentServiceImpl implements StudentService{ private StudentDao studentDao; public void setStudentDao(StudentDao studentDao) {
this.studentDao = studentDao;
} @Override
public int addStudent(Student student) {
return studentDao.addStudent(student);
} @Override
public int updateStudent(Student student) {
return studentDao.updateStudent(student);
} @Override
public int deleteStudent(int id) {
return studentDao.deleteStudent(id);
} @Override
public List<Student> findStudents() {
return studentDao.findStudents();
} }
StudentService.java:
package com.wishwzp.service;
import java.util.List;
import com.wishwzp.model.Student;
public interface StudentService {
public int addStudent(Student student);
public int updateStudent(Student student);
public int deleteStudent(int id);
public List<Student> findStudents();
}
StudentDaoImpl.java:
package com.wishwzp.dao.impl; import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List; import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowCallbackHandler; import com.wishwzp.dao.StudentDao;
import com.wishwzp.model.Student; public class StudentDaoImpl implements StudentDao{ private JdbcTemplate jdbcTemplate; public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
this.jdbcTemplate = jdbcTemplate;
} @Override
public int addStudent(Student student) {
String sql="insert into t_student values(null,?,?)";
Object []params=new Object[]{student.getName() , student.getAge()};
int addjdbcTemplate = jdbcTemplate.update(sql,params);
return addjdbcTemplate;
} @Override
public int updateStudent(Student student) {
String sql="update t_student set name=?,age=? where id=?";
Object []params=new Object[]{student.getName() , student.getAge() , student.getId()};
int updatejdbcTemplate = jdbcTemplate.update(sql,params);
return updatejdbcTemplate;
} @Override
public int deleteStudent(int id) {
String sql="delete from t_student where id=?";
Object []params=new Object[]{ id };
int deletejdbcTemplate = jdbcTemplate.update(sql,params);
return deletejdbcTemplate;
} @Override
public List<Student> findStudents() {
String sql="select * from t_student";
final List<Student> studentList=new ArrayList<Student>();
jdbcTemplate.query(sql, new RowCallbackHandler(){ @Override
public void processRow(ResultSet rs) throws SQLException {
Student student=new Student();
student.setId(rs.getInt("id"));
student.setName(rs.getString("name"));
student.setAge(rs.getInt("age"));
studentList.add(student);
}
});
return studentList;
} }
StudentDao.java:
package com.wishwzp.dao;
import java.util.List;
import com.wishwzp.model.Student;
public interface StudentDao {
public int addStudent(Student student);
public int updateStudent(Student student);
public int deleteStudent(int id);
public List<Student> findStudents();
}
Student.java:
package com.wishwzp.model;
public class Student {
private int id;
private String name;
private int age;
public Student() {
super();
// TODO Auto-generated constructor stub
}
public Student(String name, int age) {
super();
this.name = name;
this.age = age;
}
public Student(int id, String name, int age) {
super();
this.id = id;
this.name = name;
this.age = age;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
@Override
public String toString() {
return "Student [id=" + id + ", name=" + name + ", age=" + age + "]";
}
}
运行结果就是每一个对数据库的CRUD
3，JdbcDaoSupport 的使用；
T.java:
package com.wishwzp.test; import java.util.List; import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext; import com.wishwzp.model.Student;
import com.wishwzp.service.StudentService; public class T { private ApplicationContext ac; @Before
public void setUp() throws Exception {
ac=new ClassPathXmlApplicationContext("beans.xml");
} @Test
public void addStudent() {
StudentService studentService=(StudentService)ac.getBean("studentService");
int addNums=studentService.addStudent(new Student("王五", 1));
if(addNums==1){
System.out.println("添加成功");
}
} @Test
public void updateStudent() {
StudentService studentService=(StudentService)ac.getBean("studentService");
int updateNums=studentService.updateStudent(new Student(4,"王五2", 2));
if(updateNums==1){
System.out.println("更新成功");
}
} @Test
public void deleteStudent() {
StudentService studentService=(StudentService)ac.getBean("studentService");
int deleteNums=studentService.deleteStudent(10);
if(deleteNums==1){
System.out.println("删除成功");
}
} @Test
public void findStudents() {
StudentService studentService=(StudentService)ac.getBean("studentService");
List<Student> studentList=studentService.findStudents();
for(Student student:studentList){
System.out.println(student);
}
} }
beans.xml:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd"> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<property name="driverClassName" value="${jdbc.driverClassName}"/>
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
</bean> <context:property-placeholder location="jdbc.properties"/> <bean id="studentDao" class="com.wishwzp.dao.impl.StudentDaoImpl">
<property name="dataSource" ref="dataSource"></property>
</bean> <bean id="studentService" class="com.wishwzp.service.impl.StudentServiceImpl">
<property name="studentDao" ref="studentDao"></property>
</bean> </beans>
jdbc.properties:
jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/db_spring?characterEncoding=utf-8
jdbc.username=root
jdbc.password=root
StudentServiceImpl.java:
package com.wishwzp.service.impl; import java.util.List; import com.wishwzp.dao.StudentDao;
import com.wishwzp.model.Student;
import com.wishwzp.service.StudentService; public class StudentServiceImpl implements StudentService{ private StudentDao studentDao; public void setStudentDao(StudentDao studentDao) {
this.studentDao = studentDao;
} @Override
public int addStudent(Student student) {
return studentDao.addStudent(student);
} @Override
public int updateStudent(Student student) {
return studentDao.updateStudent(student);
} @Override
public int deleteStudent(int id) {
return studentDao.deleteStudent(id);
} @Override
public List<Student> findStudents() {
return studentDao.findStudents();
} }
StudentService.java:
package com.wishwzp.service;
import java.util.List;
import com.wishwzp.model.Student;
public interface StudentService {
public int addStudent(Student student);
public int updateStudent(Student student);
public int deleteStudent(int id);
public List<Student> findStudents();
}
StudentDaoImpl.java:
package com.wishwzp.dao.impl; import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List; import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowCallbackHandler;
import org.springframework.jdbc.core.support.JdbcDaoSupport; import com.wishwzp.dao.StudentDao;
import com.wishwzp.model.Student; public class StudentDaoImpl extends JdbcDaoSupport implements StudentDao{ @Override
public int addStudent(Student student) {
String sql="insert into t_student values(null,?,?)";
Object []params=new Object[]{student.getName(),student.getAge()};
int addgetJdbcTemplate = getJdbcTemplate().update(sql,params);
return addgetJdbcTemplate;
//return this.getJdbcTemplate().update(sql,params);
} @Override
public int updateStudent(Student student) {
String sql="update t_student set name=?,age=? where id=?";
Object []params=new Object[]{student.getName() , student.getAge() , student.getId()};
int updategetJdbcTemplate = getJdbcTemplate().update(sql,params);
return updategetJdbcTemplate;
//return this.getJdbcTemplate().update(sql,params);
} @Override
public int deleteStudent(int id) {
String sql="delete from t_student where id=?";
Object []params=new Object[]{id};
int deletegetJdbcTemplate = getJdbcTemplate().update(sql,params);
return deletegetJdbcTemplate;
//return this.getJdbcTemplate().update(sql,params);
} @Override
public List<Student> findStudents() {
String sql="select * from t_student";
final List<Student> studentList=new ArrayList<Student>();
this.getJdbcTemplate().query(sql, new RowCallbackHandler(){ @Override
public void processRow(ResultSet rs) throws SQLException {
Student student=new Student();
student.setId(rs.getInt("id"));
student.setName(rs.getString("name"));
student.setAge(rs.getInt("age"));
studentList.add(student);
} });
return studentList;
} }
StudentDao.java:
package com.wishwzp.dao;
import java.util.List;
import com.wishwzp.model.Student;
public interface StudentDao {
public int addStudent(Student student);
public int updateStudent(Student student);
public int deleteStudent(int id);
public List<Student> findStudents();
}
Student.java:
package com.wishwzp.model;
public class Student {
private int id;
private String name;
private int age;
public Student() {
super();
// TODO Auto-generated constructor stub
}
public Student(String name, int age) {
super();
this.name = name;
this.age = age;
}
public Student(int id, String name, int age) {
super();
this.id = id;
this.name = name;
this.age = age;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
@Override
public String toString() {
return "Student [id=" + id + ", name=" + name + ", age=" + age + "]";
}
}
运行结果就是每一个对数据库的CRUD
4，NamedParameterJdbcTemplate 的使用；支持命名参数变量；
T.java:
package com.wishwzp.test; import java.util.List; import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext; import com.wishwzp.model.Student;
import com.wishwzp.service.StudentService; public class T { private ApplicationContext ac; @Before
public void setUp() throws Exception {
ac=new ClassPathXmlApplicationContext("beans.xml");
} @Test
public void addStudent() {
StudentService studentService=(StudentService)ac.getBean("studentService");
int addNums=studentService.addStudent(new Student("王五", 1));
if(addNums==1){
System.out.println("添加成功");
}
} @Test
public void updateStudent() {
StudentService studentService=(StudentService)ac.getBean("studentService");
int updateNums=studentService.updateStudent(new Student(11,"王五2", 2));
if(updateNums==1){
System.out.println("更新成功");
}
} @Test
public void deleteStudent() {
StudentService studentService=(StudentService)ac.getBean("studentService");
int deleteNums=studentService.deleteStudent(11);
if(deleteNums==1){
System.out.println("删除成功");
}
} @Test
public void findStudents() {
StudentService studentService=(StudentService)ac.getBean("studentService");
List<Student> studentList=studentService.findStudents();
for(Student student:studentList){
System.out.println(student);
}
} }
beans.xml:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd"> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<property name="driverClassName" value="${jdbc.driverClassName}"/>
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
</bean> <context:property-placeholder location="jdbc.properties"/> <bean id="namedParameterJdbcTemplate" class="org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate">
<constructor-arg ref="dataSource"></constructor-arg>
</bean> <bean id="studentDao" class="com.wishwzp.dao.impl.StudentDaoImpl">
<property name="namedParameterJdbcTemplate" ref="namedParameterJdbcTemplate"></property>
</bean> <bean id="studentService" class="com.wishwzp.service.impl.StudentServiceImpl">
<property name="studentDao" ref="studentDao"></property>
</bean> </beans>
jdbc.properties:
jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/db_spring?characterEncoding=utf-8
jdbc.username=root
jdbc.password=root
StudentServiceImpl.java:
package com.wishwzp.service.impl; import java.util.List; import com.wishwzp.dao.StudentDao;
import com.wishwzp.model.Student;
import com.wishwzp.service.StudentService; public class StudentServiceImpl implements StudentService{ private StudentDao studentDao; public void setStudentDao(StudentDao studentDao) {
this.studentDao = studentDao;
} @Override
public int addStudent(Student student) {
return studentDao.addStudent(student);
} @Override
public int updateStudent(Student student) {
return studentDao.updateStudent(student);
} @Override
public int deleteStudent(int id) {
return studentDao.deleteStudent(id);
} @Override
public List<Student> findStudents() {
return studentDao.findStudents();
} }
StudentService.java:
package com.wishwzp.service;
import java.util.List;
import com.wishwzp.model.Student;
public interface StudentService {
public int addStudent(Student student);
public int updateStudent(Student student);
public int deleteStudent(int id);
public List<Student> findStudents();
}
StudentDaoImpl.java:
package com.wishwzp.dao.impl; import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List; import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowCallbackHandler;
import org.springframework.jdbc.core.namedparam.MapSqlParameterSource;
import org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate; import com.wishwzp.dao.StudentDao;
import com.wishwzp.model.Student; public class StudentDaoImpl implements StudentDao{ private NamedParameterJdbcTemplate namedParameterJdbcTemplate; public void setNamedParameterJdbcTemplate(
NamedParameterJdbcTemplate namedParameterJdbcTemplate) {
this.namedParameterJdbcTemplate = namedParameterJdbcTemplate;
} @Override
public int addStudent(Student student) {
String sql="insert into t_student values(null,:name,:age)";
MapSqlParameterSource sps=new MapSqlParameterSource();
sps.addValue("name", student.getName());
sps.addValue("age", student.getAge());
return namedParameterJdbcTemplate.update(sql,sps);
} @Override
public int updateStudent(Student student) {
String sql="update t_student set name=:name,age=:age where id=:id";
MapSqlParameterSource sps=new MapSqlParameterSource();
sps.addValue("name", student.getName());
sps.addValue("age", student.getAge());
sps.addValue("id", student.getId());
return namedParameterJdbcTemplate.update(sql,sps);
} @Override
public int deleteStudent(int id) {
String sql="delete from t_student where id=:id";
MapSqlParameterSource sps=new MapSqlParameterSource();
sps.addValue("id", id);
return namedParameterJdbcTemplate.update(sql,sps);
} @Override
public List<Student> findStudents() {
String sql="select * from t_student";
final List<Student> studentList=new ArrayList<Student>();
namedParameterJdbcTemplate.query(sql, new RowCallbackHandler(){ @Override
public void processRow(ResultSet rs) throws SQLException {
Student student=new Student();
student.setId(rs.getInt("id"));
student.setName(rs.getString("name"));
student.setAge(rs.getInt("age"));
studentList.add(student);
} });
return studentList;
} }
StudentDao.java:
package com.wishwzp.dao;
import java.util.List;
import com.wishwzp.model.Student;
public interface StudentDao {
public int addStudent(Student student);
public int updateStudent(Student student);
public int deleteStudent(int id);
public List<Student> findStudents();
}
Student.java:
package com.wishwzp.model;
public class Student {
private int id;
private String name;
private int age;
public Student() {
super();
// TODO Auto-generated constructor stub
}
public Student(String name, int age) {
super();
this.name = name;
this.age = age;
}
public Student(int id, String name, int age) {
super();
this.id = id;
this.name = name;
this.age = age;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
@Override
public String toString() {
return "Student [id=" + id + ", name=" + name + ", age=" + age + "]";
}
}
运行结果就是每一个对数据库的CRUD
第二节：Spring 对Hibernate 的支持
后面Spring 整合Hibernate 的时候会提的。
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