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假如我有一个dto，里面有个student类，这个student类的属性是跟数据库中stuinfo是一一对应的，那么如果我现在对这个stuinfo表增删除一些字段，如何能够快速的重写这个sutdent类，以下贴上代码
package com.hcj.test;import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Date; public class GenEntityOracle { private String packageOutPath = "com.hcj.test";//指定实体生成所在包的路径 private String javaName = "Student"; //.java文件名private String authorName = "风飘过不留痕";//作者名字 private String tablename = "stuinfo";//表名 private String[] colnames; // 列名数组 private String[] colTypes; //列名类型数组 private int[] colSizes; //列名大小数组 private boolean f_util = false; // 是否需要导入包java.util.* private boolean f_sql = false; // 是否需要导入包java.sql.* //数据库连接 private static final String URL ="jdbc:oracle:thin:@127.0.0.1:1521/orcl"; private static final String NAME = "scott"; private static final String PASS = "123456"; private static final String DRIVER ="oracle.jdbc.driver.OracleDriver"; /* * 构造函数 */ public GenEntityOracle(){ //创建连接 Connection con; //查要生成实体类的表 String sql = "select * from " + tablename; Statement pStemt = null; try { try { //加载驱动Class.forName(DRIVER); } catch (ClassNotFoundException e1) { e1.printStackTrace(); } //链接数据库con = DriverManager.getConnection(URL,NAME,PASS); pStemt = (Statement) con.createStatement(); ResultSet rs = pStemt.executeQuery(sql); ResultSetMetaData rsmd = rs.getMetaData(); int size = rsmd.getColumnCount(); //统计列 colnames = new String[size]; colTypes = new String[size]; colSizes = new int[size]; for (int i = 0; i < size; i++) { colnames[i] = rsmd.getColumnName(i + 1); colTypes[i] = rsmd.getColumnTypeName(i + 1); if(colTypes[i].equalsIgnoreCase("date") || colTypes[i].equalsIgnoreCase("timestamp")){ f_util = true; } if(colTypes[i].equalsIgnoreCase("blob") || colTypes[i].equalsIgnoreCase("char")){ f_sql = true; } colSizes[i] = rsmd.getColumnDisplaySize(i + 1); } String content = parse(colnames,colTypes,colSizes); try { File directory = new File(""); String outputPath = directory.getAbsolutePath()+ "/src/"+this.packageOutPath.replace(".", "/")+"/"+ javaName + ".java"; FileWriter fw = new FileWriter(outputPath); PrintWriter pw = new PrintWriter(fw); pw.println(content); pw.flush(); pw.close(); } catch (IOException e) { e.printStackTrace(); } } catch (SQLException e) { e.printStackTrace(); } finally{
// try {
// con.close();
// } catch (SQLException e) {
// // TODO Auto-generated catch block
// e.printStackTrace();
// } } } /** * 功能：生成实体类主体代码 * @param colnames * @param colTypes * @param colSizes * @return */ private String parse(String[] colnames, String[] colTypes, int[] colSizes) { StringBuffer sb = new StringBuffer(); //导入包名sb.append("package " + this.packageOutPath + ";\r\n"); //判断是否导入工具包 if(f_util){ sb.append("import java.util.Date;\r\n"); } if(f_sql){ sb.append("import java.sql.*;\r\n"); } sb.append("\r\n"); //注释部分 sb.append(" /**\r\n"); sb.append(" * "+ javaName +" 实体类\r\n"); sb.append(" * "+new Date()+" "+this.authorName+"\r\n"); sb.append(" */ \r\n"); //实体部分 sb.append("\r\n\r\npublic class " + javaName + "{\r\n"); processAllAttrs(sb);//属性 processAllMethod(sb);//get set方法 processAllConstructor(sb); //生成有参和无参构造方法sb.append("}\r\n"); return sb.toString(); } /** * 功能：生成所有属性 * @param sb */ private void processAllAttrs(StringBuffer sb) { for (int i = 0; i < colnames.length; i++) { sb.append("\tprivate " + sqlType2JavaType(colTypes[i]) + " " + colnames[i].toLowerCase() + ";\r\n"); } //换行sb.append("\r\n");} /** * 功能：生成所有方法 * @param sb */ private void processAllMethod(StringBuffer sb) { for (int i = 0; i < colnames.length; i++) { //生成set方法sb.append("\tpublic void set" + initcap(colnames[i].toLowerCase()) + "(" + sqlType2JavaType(colTypes[i]) + " " + colnames[i].toLowerCase() + "){\r\n"); sb.append("\t\tthis." + colnames[i].toLowerCase() + "=" + colnames[i].toLowerCase() + ";\r\n"); sb.append("\t}\r\n\r\n");//生成get方法sb.append("\tpublic " + sqlType2JavaType(colTypes[i]) + " get" + initcap(colnames[i].toLowerCase()) + "(){\r\n"); sb.append("\t\treturn " + colnames[i].toLowerCase() + ";\r\n"); sb.append("\t}\r\n\r\n"); } } /** * 功能：生成无参和有参构造方法* @param sb */ private void processAllConstructor(StringBuffer sb){//生成无参构造方法sb.append("\tpublic " + javaName + "(){\r\n");sb.append("\t\tsuper();\r\n");sb.append("\t}\r\n\r\n");//生成有参构造函数sb.append("\tpublic " + javaName + "(");for (int i = 0; i < colnames.length; i++) { if(i == colnames.length - 1){sb.append(sqlType2JavaType(colTypes[i].toLowerCase()) + " " + colnames[i].toLowerCase() + "){\r\n");}else{sb.append(sqlType2JavaType(colTypes[i].toLowerCase()) + " " + colnames[i].toLowerCase() + ", "); }}//函数内容for (int i = 0; i < colnames.length; i++) { sb.append("\t\tthis." + colnames[i].toLowerCase() + " = " + colnames[i].toLowerCase() + ";\r\n");}sb.append("\t}");//换行sb.append("\r\n");}/** * 功能：将输入字符串的首字母改成大写 * @param str * @return */ private String initcap(String str) { char[] ch = str.toCharArray(); if(ch[0] >= 'a' && ch[0] <= 'z'){ ch[0] = (char)(ch[0] - 32); } return new String(ch); } /** * 功能：获得列的数据类型 ,转化为java中的类型* @param sqlType * @return */ private String sqlType2JavaType(String sqlType) { if(sqlType.equalsIgnoreCase("binary_double")){ return "double"; }else if(sqlType.equalsIgnoreCase("binary_float")){ return "float"; }else if(sqlType.equalsIgnoreCase("blob")){ return "byte[]"; }else if(sqlType.equalsIgnoreCase("blob")){ return "byte[]"; }else if(sqlType.equalsIgnoreCase("char") || sqlType.equalsIgnoreCase("nvarchar2") || sqlType.equalsIgnoreCase("varchar2")){ return "String"; }else if(sqlType.equalsIgnoreCase("date") || sqlType.equalsIgnoreCase("timestamp") || sqlType.equalsIgnoreCase("timestamp with local time zone") || sqlType.equalsIgnoreCase("timestamp with time zone")){ return "Date"; }else if(sqlType.equalsIgnoreCase("number")){ return "Long"; } return "String"; } /** * 出口 * TODO * @param args */ public static void main(String[] args) { new GenEntityOracle(); } }转载请注明出处：http://www.cnblogs.com/freeliver54/archive/2013/04/15/3023195.html（这里我在原来的基础上个属性变为小写并添加了有参和无参构造）
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