zoukankan      html  css  js  c++  java
  • Spring JdbcTemplate小结

    提供了JdbcTemplate 来封装数据库jdbc操作细节: 
    包括: 数据库连接[打开/关闭] ,异常转义 ,SQL执行 ,查询结果的转换 

    使用模板方式封装 jdbc数据库操作-固定流程的动作,提供丰富callback回调接口功能,方便用户自定义加工细节,更好模块化jdbc操作,简化传统的JDBC操作的复杂和繁琐过程。 

    1) 使用JdbcTemplate 更新(insert /update /delete)

    1 int k = jdbcTemplate.update("UPDATE tblname SET prop1=?,prop2=?..."newObject[]{...});
    1 jdbcTemplate.update("INSERT INTO tblname VALUES(?,?,..)"new Object[]{...},
    2      new int[]{Types.VARCHAR,Types.NUMERIC});
    01 jdbcTemplate.update("INSERT INTO tblname VALUES(?,?,..)",                    
    02         newPreparedStatementSetter(){                         
    03                public void setValues(PreparedStatement ps) throwsSQLException{     
    04                     ps.setLong(1, user.getId(1));
    05                     ps.setString(2, user.getName(2));  
    06                     ps.setDate(3new java.sql.Date(newDate().getTime()); 
    07                     ps.setTimestamp(4new Timestamp(new Date().getTime());
    08                }                    
    09         }
    10 );


    2) 使用JdbcTemplate 查询 (select)

    1 final User user = newUser();
    2 jdbcTemplate.query("SELECT id,name,.. FROM tblname WHERE id=1",
    3        newRowCallbackHandler(){
    4               public void processRow(ResultSet rs) throwsSQLException{
    5                     user.setId(rs.getLong(1));
    6                     user.setName(rs.getString(2));
    7               }
    8       }
    9 );
    01 List uGroup = jdbcTemplate.query("SELECT id,name,.. FROM tblname WHERE igroup=1",
    02      newRowMapper(){
    03             public Object mapRow(ResultSet rs,int no) throwsSQLException{
    04                      User user = newUser();
    05                      user.setId(rs.getLong(1));
    06                      user.setName(rs.getString(2));
    07                      returnuser ;
    08             }
    09      }
    10 };


    3)使用JdbcTemplate 便捷方法

    1 List uNames = jdbcTemplate.queryForList("SELECT name FROM tblname WHERE id>?",
    2     new Integer []{5}, String.class);
    1 List<Map> uMapList = (List<Map>) jdbcTemplate.queryForList( "SELECT id, name FROM tblname WHERE id>?",
    2              newInteger []{5});
    3 for(Map<String,Object> uMap :uMapList){
    4       Integer id = uMap.get("id");
    5       String name = uMap.get("name");
    6 };
    1 String user = jdbcTemplate.queryForObject("SELECT name FROM tblname WHERE id=?",
    2      new Integer []{5}, String.class );
    1 intuNum = jdbcTemplate.queryForInt("SELECT count(*) FROM tblname WHERE id>?",
    2     new Integer []{5});



    4)使用jdbc 操作类

    a)扩展 MappingSqlQuery类

    01 class JdbcQueryObject extends MappingSqlQuery { // extends SqlQuery
    02       public JdbcQueryObject (DataSource ds,String sql){
    03             this.setDataSource( ds );
    04             this.setSql( sql );
    05             this.declareParameter(newSqlparameter("propName",
    06                 Types.VARCHAR);// propName 提示作用
    07         this.compile();
    08       }
    09       public Object mapRow(ResultSet rs,int p) throws SQLException{
    10                  // ...
    11      }
    12 }
    13 JdbcQueryObject queryObj = new JdbcQueryObject( ds,
    14       "SELECT .. FROM tblName WHERE param=?");
    15 List list = queryObj.execute(new Object[]{...});

    b)使用 SqlFunction 类 查询单条结果

    1 SqlFunction queryFun = newSqlFunction( ds,
    2       "select count(*) from tblName where ..." ,new int[]{Types.CHAR,...} );
    3 queryFun.compile();
    4 queryFun.run(new Object[]{p1,p2,..});

    c)使用 SqlUpdate 类 更新

    1 SqlUpdate updateFunc = new SqlUpdate(ds ,"INSERT tblName ...");
    2 updateFunc.declareParameter( new SqlParameter("prop",Types.CHAR) );
    3 updateFunc.compile();
    4 updateFunc.update(new String[]{s1,s1});

    5)支持jdbc 事务

    spring的事务管理有两种方式:编程式事务、声明式事务

    这里谈一下 基于数据库单一资源的编程式事务:

    spring用实现TransactionDefinition接口的类定义事务的属性:传播行为;隔离级别;超时值;只读标志

    默认实现为:DefaultTransactionDefinition类

    01 PlatformTransactionManager tm = 
    02 newDataSourceTransactionManager(
    03             jdbcTemplate.getDataSource() );
    04 TransactionStatus status = null;
    05 try{
    06     //null 默认事务属性配置DefaultTransactionDefinition
    07     status = tm.getTransaction(null);          
    08   for(finalString wd: words){         
    09    try {
    10      jdbcTemplate.update( insertWordSql,
    11           new PreparedStatementSetter(){
    12  
    13     public voidsetValues(PreparedStatement pstate)
    14                      throws SQLException {
    15                 pstate.setString(1, wd) ;
    16         pstate.setTimestamp(2,
    17         new Timestamp( newDate().getTime() ));                            
    18     }                  
    19         }
    20      );                
    21              
    22    catch (DataAccessException e) {
    23        e.printStackTrace();
    24        //tm.rollback(status);
    25     }
    26     // end for
    27 finally {
    28      tm.commit(status);
    29 }  

    转自:http://hwqjavaeye.iteye.com/blog/289330

  • 相关阅读:
    7月的尾巴,你是XXX
    戏说Android view 工作流程《下》
    “燕子”
    Android开机动画bootanimation.zip
    戏说Android view 工作流程《上》
    ViewController里已连接的IBOutlet为什么会是nil
    My first App "Encrypt Wheel" is Ready to Download!
    iOS开发中角色Role所产生的悲剧(未完)
    UIScrollView实现不全屏分页的小技巧
    Apple misunderstood my app,now my app status changed to “In Review”
  • 原文地址:https://www.cnblogs.com/a757956132/p/3900559.html
Copyright © 2011-2022 走看看