Spring中jdbcTemplate的用法实例（一）

Spring中jdbcTemplate的用法实例（一）

一、首先配置JdbcTemplate；

要使用Jdbctemplate 对象来完成jdbc 操作。通常情况下，有三种种方式得到JdbcTemplate 对象。 

      第一种方式：我们可以在自己定义的DAO 实现类中注入一个DataSource 引用来完 成JdbcTemplate 的实例化。也就是它是从外部“注入” DataSource 到DAO 中，然后 自己实例化JdbcTemplate，然后将DataSource 设置到JdbcTemplate 对象中。 

      第二种方式： 在 Spring 的 IoC 容器中配置一个 JdbcTemplate 的 bean，将 DataSource 注入进来，然后再把JdbcTemplate 注入到自定义DAO 中。 

      第三种方式: Spring 提供了 org.springframework.jdbc.core.support.JdbcDaoSupport 类 ， 这 个 类 中 定 义 了 JdbcTemplate 属性，也定义了DataSource 属性，当设置DataSource 属性的时候，会创 建jdbcTemplate 的实例，所以我们自己编写的DAO 只需要继承JdbcDaoSupport 类， 然后注入DataSource
即可。提倡采用第三种方法。虽然下面的用法中采用了前两种方法

  配置方法有3种：

 连接地址： http://lehsyh.iteye.com/blog/1579737
使用方法:

/**
* 创建表
*/
public void create(String tableName){ //tb_test1
jdbcTemplate.execute("create table "+tableName +" (id integer,user_name varchar2(40),password varchar2(40))");
}

//jdbcTemplate.update适合于insert 、update和delete操作；
/**
* 第一个参数为执行sql
* 第二个参数为参数数据
*/
public void save3(User user) {
Assert.isNull(user, "user is not null");
jdbcTemplate.update("insert into tb_test1(name,password) values(?,?)",
new Object[]{user.getUsername(),user.getPassword()});
}

/**
* 第一个参数为执行sql
* 第二个参数为参数数据
* 第三个参数为参数类型
*/
@Override
public void save(User user) {
Assert.isNull(user, "user is not null");
jdbcTemplate.update(
"insert into tb_test1(name,password) values(?,?)",
new Object[]{user.getUsername(),user.getPassword()},
new int[]{java.sql.Types.VARCHAR,java.sql.Types.VARCHAR}
);
}

//避免sql注入
public void save2(final User user) {
Assert.isNull(user, "user is not null");

jdbcTemplate.update("insert into tb_test1(name,password) values(?,?)",
new PreparedStatementSetter(){

@Override
public void setValues(PreparedStatement ps) throws SQLException {
ps.setString(1, user.getUsername());
ps.setString(2, user.getPassword());
}
});

}

public void save4(User user) {
Assert.isNull(user, "user is not null");
jdbcTemplate.update("insert into tb_test1(name,password) values(?,?)",
new Object[]{user.getUsername(),user.getPassword()});
}

//返回插入的主键
public List save5(final User user) {

KeyHolder keyHolder = new GeneratedKeyHolder();

jdbcTemplate.update(new PreparedStatementCreator() {

@Override
public PreparedStatement createPreparedStatement(Connection connection) throws SQLException {
PreparedStatement ps = connection.prepareStatement("insert into tb_test1(name,password) values(?,?)", new String[] {"id"});
ps.setString(1, user.getUsername());
ps.setString(2, user.getPassword());
return ps;
}
},
keyHolder);

return keyHolder.getKeyList();
}

@Override
public void update(final User user) {
jdbcTemplate.update(
"update tb_test1 set name=？,password=？ where id = ?",
new PreparedStatementSetter(){
@Override
public void setValues(PreparedStatement ps) throws SQLException {
ps.setString(1, user.getUsername());
ps.setString(2, user.getPassword());
ps.setInt(3, user.getId());
}
}
);
}

@Override
public void delete(User user) {
Assert.isNull(user, "user is not null");
jdbcTemplate.update(
"delete from tb_test1 where id = ?",
new Object[]{user.getId()},
new int[]{java.sql.Types.INTEGER});
}

@Deprecated //因为没有查询条件，所以用处不大
public int queryForInt1(){
return jdbcTemplate.queryForInt("select count(0) from tb_test1");
}

public int queryForInt2(User user){
return jdbcTemplate.queryForInt("select count(0) from tb_test1 where username = ?" ,
new Object[]{user.getUsername()});
}

//最全的参数3个
public int queryForInt3(User user){
return jdbcTemplate.queryForInt("select count(0) from tb_test1 where username = ?" ,
new Object[]{user.getUsername()},
new int[]{java.sql.Types.VARCHAR});
}

//可以返回是一个基本类型的值
@Deprecated //因为没有查询条件，所以用处不大
public String queryForObject1(User user) {
return (String) jdbcTemplate.queryForObject("select username from tb_test1 where id = 100",
String.class);
}

//可以返回值是一个对象
@Deprecated //因为没有查询条件，所以用处不大
public User queryForObject2(User user) {
return (User) jdbcTemplate.queryForObject("select * from tb_test1 where id = 100", User.class); //class是结果数据的java类型
}

@Deprecated //因为没有查询条件，所以用处不大
public User queryForObject3(User user) {
return (User) jdbcTemplate.queryForObject("select * from tb_test1 where id = 100",
new RowMapper(){

@Override
public Object mapRow(ResultSet rs, int rowNum)throws SQLException {
User user = new User();
user.setId(rs.getInt("id"));
user.setUsername(rs.getString("username"));
user.setPassword(rs.getString("password"));
return user;
}
}
);
}

public User queryForObject4(User user) {
return (User) jdbcTemplate.queryForObject("select * from tb_test1 where id = ?",
new Object[]{user.getId()},
User.class); //class是结果数据的java类型 实际上这里是做反射，将查询的结果和User进行对应复制
}

public User queryForObject5(User user) {
return (User) jdbcTemplate.queryForObject(
"select * from tb_test1 where id = ?",
new Object[]{user.getId()},
new RowMapper(){

@Override
public Object mapRow(ResultSet rs,int rowNum)throws SQLException {
User user = new User();
user.setId(rs.getInt("id"));
user.setUsername(rs.getString("username"));
user.setPassword(rs.getString("password"));
return user;
}

}); //class是结果数据的java类型
}

@Override
public User queryForObject(User user) {
//方法有返回值
return (User) jdbcTemplate.queryForObject("select * from tb_test1 where id = ?",
new Object[]{user.getId()},
new int[]{java.sql.Types.INTEGER},
new RowMapper() {

@Override
public Object mapRow(ResultSet rs, int rowNum) throws SQLException {
User user = new User();
user.setId(rs.getInt("id"));
user.setUsername(rs.getString("username"));
user.setPassword(rs.getString("password"));
return user;
}
}
);
}

@SuppressWarnings("unchecked")
public List<User> queryForList1(User user) {
return (List<User>) jdbcTemplate.queryForList("select * from tb_test1 where username = ?",
new Object[]{user.getUsername()},
User.class);
}

@SuppressWarnings("unchecked")
public List<String> queryForList2(User user) {
return (List<String>) jdbcTemplate.queryForList("select username from tb_test1 where sex = ?",
new Object[]{user.getSex()},
String.class);
}

@SuppressWarnings("unchecked")
//最全的参数查询
public List<User> queryForList3(User user) {
return (List<User>) jdbcTemplate.queryForList("select * from tb_test1 where username = ?",
new Object[]{user.get
bfeb
Username()},
new int[]{java.sql.Types.VARCHAR},
User.class);
}

//通过RowCallbackHandler对Select语句得到的每行记录进行解析，并为其创建一个User数据对象。实现了手动的OR映射。
public User queryUserById4(String id){
final User user = new User();

//该方法返回值为void
this.jdbcTemplate.query("select * from tb_test1 where id = ?",
new Object[] { id },
new RowCallbackHandler() {

@Override
public void processRow(ResultSet rs) throws SQLException {
User user = new User();
user.setId(rs.getInt("id"));
user.setUsername(rs.getString("username"));
user.setPassword(rs.getString("password"));
}
});

return user;
}

@SuppressWarnings("unchecked")
@Override
public List<User> list(User user) {
return jdbcTemplate.query("select * from tb_test1 where username like '%?%'",
new Object[]{user.getUsername()},
new int[]{java.sql.Types.VARCHAR},
new RowMapper(){

@Override
public Object mapRow(ResultSet rs, int rowNum) throws SQLException {
User user = new User();
user.setId(rs.getInt("id"));
user.setUsername(rs.getString("username"));
user.setPassword(rs.getString("password"));
return user;
}
});
}

//批量操作 适合于增、删、改操作
public int[] batchUpdate(final List users) {

int[] updateCounts = jdbcTemplate.batchUpdate(
"update tb_test1 set username = ?, password = ? where id = ?",
new BatchPreparedStatementSetter() {

@Override
public void setValues(PreparedStatement ps, int i) throws SQLException {
ps.setString(1, ((User)users.get(i)).getUsername());
ps.setString(2, ((User)users.get(i)).getPassword());
ps.setLong(3, ((User)users.get(i)).getId());
}

@Override
public int getBatchSize() {
return users.size();
}
}
);

return updateCounts;
}

//调用存储过程
public void callProcedure(int id){
this.jdbcTemplate.update("call SUPPORT.REFRESH_USERS_SUMMARY(?)", new Object[]{Long.valueOf(id)});
}