我对SpringDAO层支持的总结

之前发过两篇关于Spring的总结帖子 反响还不错，再把剩下的几篇发上来。共享给大家。

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我对IoC/DI的理解

我对AOP的理解

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public interface JdbcOperations { //接口定义行为集 public Object execute() throws SQLException ;}?

public abstract class AbstractJdbcOperations implements JdbcOperations {    @Override    public final Object execute() throws SQLException {       Connection conn = DataSourceUtils.getConnection();        try {            Object retVal = doInConnection(conn);            conn.commit();            return retVal;        }catch (Exception e) {   conn.rollback(); throw e;}        finally {                          conn.close(); }    }    public abstract Object doInConnection(Connection conn) throws SQLException;}?

public class DataSourceUtils {    public static Connection getConnection() {        //返回数据库连接        return null;    }}

JdbcOperations select = new AbstractJdbcOperations() { @Override public Object doInConnection(Connection conn) throws SQLException { PreparedStatement pstmt = conn.prepareStatement("select * from tbl_user"); ResultSet rs = pstmt.executeQuery(); List result = null; //处理结果集 return result; } }; select.execute();?public interface JdbcOprations2 { //接口定义行为集 public Object execute(ConnectionCallback callback) throws Exception ;}

public interface ConnectionCallback {    public Object doInConnection(Connection conn) throws SQLException;}?

public class JdbcTemplate implements JdbcOprations2 {    @Override    public Object execute(ConnectionCallback callback) throws Exception {        Connection conn = DataSourceUtils.getConnection();        try {            Object retVal = callback.doInConnection(conn);            conn.commit();            return retVal;        }        catch (Exception e) {            conn.rollback();            throw e;        }        finally {            conn.close();        }    }    }?

jdbcTemplate.execute(new ConnectionCallback() {                        @Override            public Object doInConnection(Connection conn) throws SQLException {                //可变操作                return null;            }        });?

public interface PreparedStatementCallback {    public Object doInPreparedStatement(PreparedStatement pstmt)         throws  SQLException;}?

缺点：灵活但不通用?????

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