Java-KGLI工具类总结.docx

C3p0 连接池 DB工具类：JDBCUtils :package cn.kgli.utils;import java.io.InputStream;import java.lang.reflect.Field;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.ResultSetMetaData;import java.sql.SQLException;import java.sql.Statement;import java.util.ArrayList;import java.util.List;import java.util.Properties;import com.mchange.v2.c3p0.ComboPooledDataSource;public class JdbcUtils private static ComboPooledDataSource ds = null;statictry/*ds = new ComboPooledDataSource();ds.setDriverClass(com.mysql.jdbc.Driver);ds.setJdbcUrl(jdbc:mysql:/localhost:3306/day16);ds.setUser(root);ds.setPassword(root);ds.setInitialPoolSize(10);ds.setMinPoolSize(5);ds.setMaxPoolSize(20);*/ds = new ComboPooledDataSource();catch (Exception e) throw new ExceptionInInitializerError(e);public static Connection getConnection() throws SQLExceptionreturn ds.getConnection();public static void release(Connection conn,Statement st,ResultSet rs)if(rs!=null)tryrs.close();catch (Exception e) e.printStackTrace();rs = null;if(st!=null)tryst.close();catch (Exception e) e.printStackTrace();if(conn!=null)tryconn.close();catch (Exception e) e.printStackTrace();/替换dao中的增删改方法public static void update(String sql,Object params) throws SQLExceptionConnection conn = null;PreparedStatement st = null;ResultSet rs = null;tryconn = getConnection();st = conn.prepareStatement(sql);for(int i=0;iparams.length;i+)st.setObject(i+1, paramsi);st.executeUpdate();finallyrelease(conn, st, rs);/替换所有dao中的查询 策略模式public static Object query(String sql,Object params,ResultSetHandler rsh) throws SQLExceptionConnection conn = null;PreparedStatement st = null;ResultSet rs = null;tryconn = getConnection();st = conn.prepareStatement(sql);for(int i=0;iparams.length;i+)st.setObject(i+1, paramsi);rs = st.executeQuery();return rsh.handler(rs);finallyrelease(conn, st, rs);JDBCUtills_dbcp.java:package cn.kgli.utils;import java.io.InputStream;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;import java.util.Properties;import javax.sql.DataSource;import mons.dbcp.BasicDataSourceFactory;public class JdbcUtils_DBCP private static DataSource ds = null;statictryInputStream in = JdbcUtils_DBCP.class.getClassLoader().getResourceAsStream(perties);Properties prop = new Properties();prop.load(in);BasicDataSourceFactory factory = new BasicDataSourceFactory();ds = factory.createDataSource(prop);System.out.println(ds);catch (Exception e) throw new ExceptionInInitializerError(e);public static Connection getConnection() throws SQLExceptionreturn ds.getConnection();public static void release(Connection conn,Statement st,ResultSet rs)if(rs!=null)tryrs.close();catch (Exception e) e.printStackTrace();rs = null;if(st!=null)tryst.close();catch (Exception e) e.printStackTrace();if(conn!=null)tryconn.close();catch (Exception e) e.printStackTrace();/BeanHandler.javapackage cn.kgli.utils;import java.lang.reflect.Field;import java.sql.ResultSet;import java.sql.ResultSetMetaData;public class BeanHandler implements ResultSetHandler private Class clazz;public BeanHandler(Class clazz)this.clazz = clazz;public Object handler(ResultSet rs) tryif(!rs.next()return null;Object bean = clazz.newInstance();ResultSetMetaData metadata = rs.getMetaData();int columnCount = metadata.getColumnCount(); /得到结果集中有几列数据for(int i=0;icolumnCount;i+)String coulmnName = metadata.getColumnName(i+1); /得到每列的列名Object coulmnData = rs.getObject(i+1);Field f = clazz.getDeclaredField(coulmnName);/反射出类上列名对应的属性f.setAccessible(true);f.set(bean, coulmnData);return bean;catch (Exception e) throw new RuntimeException(e);BeanListHandler.javapackage cn.kgli.utils;import java.lang.reflect.Field;import java.sql.ResultSet;import java.sql.ResultSetMetaData;import java.util.ArrayList;import java.util.List;public class BeanListHandler implements ResultSetHandler private Class clazz;public BeanListHandler(Class clazz)this.clazz = clazz;public Object handler(ResultSet rs) tryList list = new ArrayList();while(rs.next()Object bean = clazz.newInstance();ResultSetMetaData metadata = rs.getMetaData();int count = metadata.getColumnCount();for(int i=0;i0?list:null;catch (Exception e) throw new RuntimeException(e);防止表单重复提交：拦截注册页面 加上session token package cn.kgli.servlet;import java.io.IOException;import java.security.MessageDigest;import java.security.NoSuchAlgorithmException;import java.util.Random;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import sun.misc.BASE64Encoder;public class FormServlet extends HttpServlet public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException String token = TokenProccessor.getInstance().makeToken();request.getSession().setAttribute(token, token); /在服务器端保存随机数request.getRequestDispatcher(/form.jsp).forward(request, response);public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException doGet(request, response);class TokenProccessor/* *单态设计模式（保证类的对象在内存中只有一个） *1、把类的构造函数私有 *2、自己创建一个类的对象 *3、对外提供一个公共的方法，返回类的对象 * */private TokenProccessor()private static final TokenProccessor instance = new TokenProccessor();public static TokenProccessor getInstance()return instance;public String makeToken() /checkException/ 7346734837483 834u938493493849384 43434384String token = (System.currentTimeMillis() + new Random().nextInt(999999999) + ;/数据指纹 128位长 16个字节 md5try MessageDigest md = MessageDigest.getInstance(md5);byte md5 = md.digest(token.getBytes();/base64编码-任意二进制编码明文字符 adfsdfsdfsfBASE64Encoder encoder = new BASE64Encoder();return encoder.encode(md5); catch (NoSuchAlgorithmException e) throw new RuntimeException(e); My JSP form.jsp starting page input type=hidden name=token value= 用户名： package cn.itcast.servlet;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class DoFormServlet extends HttpServlet public void doGet(Ht