数据库连接池（2）

 

DBUtils

环境搭建：

1、  复制库文件

c3p0的jar及c3p0-config.xml

dbuitls的jar包

mysql驱动包

2、复制并修改DBManager

CRID

插入

public void insert() throws SQLException{     QueryRunner runner = new QueryRunner(DBManager_c3p0.getDataSource()); String sql = "insert into user(id,name,password,email,birthday) values(null,?,?,?,?)";     Object[] param={"by","sss","[email protected]","1980-03-04"};     runner.update(sql, param); }

 

删除

public void delete() throws SQLException{     QueryRunner runner = new QueryRunner(DBManager_c3p0.getDataSource());     String sql = "delete from user where name=?";     Object[] param ={"by"};     runner.update(sql, param); }

 

查询

public User find() throws SQLException{     QueryRunner runner = new QueryRunner(DBManager_c3p0.getDataSource());     String sql = "select * from user where id=?";                User u = (User)runner.query(sql, newBeanHandler(User.class),1);         return u; }

 

 

public void getAll() throws SQLException{     QueryRunner runner = new QueryRunner(DBManager_c3p0.getDataSource());     String sql = "select * from user";     List<User> list = (List<User>) runner.query(sql, newBeanListHandler(User.class));     System.out.println(list.size()); }

批处理

 

public void bath() throws SQLException{     QueryRunner runner = new QueryRunner(DBManager_c3p0.getDataSource());     String sql = "insert into user(id,name,password) values(?,?,?)";     Object[][] params = {{5,"Jake","aaa"},{6,"John","bbb"},{7,"Jansen","ccc"}};     runner.batch(sql, params); }

 

 

ResultSetHandler 接口的实现类

ArrayHandler

public void testArrayHandler() throws SQLException{     QueryRunner runner = new QueryRunner(DBManager_c3p0.getDataSource());     String sql = "select * from user";     Object[] result = runner.query(sql, new ArrayHandler());     System.out.println(Arrays.asList(result)); }

ArrayListHandler

public void testArrayListHandler() throws SQLException{     QueryRunner runner = new QueryRunner(DBManager_c3p0.getDataSource());     String sql = "select * from user";     List<Object[]> result = (List<Object[]>) runner.query(sql, new ArrayListHandler());     for(int i=0; i<result.size(); i++){        System.out.println(Arrays.asList(result.get(i)));     } }

ColumnListHandler

public void testColumnListHandler() throws SQLException{     QueryRunner runner = new QueryRunner(DBManager_c3p0.getDataSource());     String sql = "select * from user";     List<Object> result = (List<Object>) runner.query(sql, new ColumnListHandler("name"));     System.out.println(result);     }

 

KeyedHandler

public void testKeyedHandler() throws SQLException{     QueryRunner runner = new QueryRunner(DBManager_c3p0.getDataSource());     String sql = "select * from user";     Map<Integer,Map<String,Object>> map = (Map) runner.query(sql, new KeyedHandler("id"));     for(Map.Entry<Integer,Map<String,Object>> me : map.entrySet()){        int id = me.getKey();        Map<String,Object> innermap = me.getValue();        for(Map.Entry<String, Object> innerme: innermap.entrySet()){            String name = innerme.getKey();            Object value = innerme.getValue();            System.out.println(name + "=" + value);                      }     } }

 

 

MapListHandler

public void testMapListHandler() throws SQLException{     QueryRunner runner = new QueryRunner(DBManager_c3p0.getDataSource());     String sql = "select * from user";     List<Map<String,Object>> result = (List<Map<String,Object>>) runner.query(sql, new MapListHandler());     for(int i=0; i<result.size(); i++){        Map<String, Object> map = result.get(i);               System.out.println("---------------------");               for(Map.Entry<String, Object> me : map.entrySet() ){            String colName = me.getKey();             Object value = me.getValue();                       System.out.println(colName + " = " + value);        }         } }