从数据库表反射出实体类，数据库表反射实体,package com.

从数据库表反射出实体类，数据库表反射实体,package com.

package com.share.barter.tool;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.PreparedStatement;import java.sql.ResultSetMetaData;import java.sql.SQLException;import java.util.Date;/** * POJO Product */public class GenEntity {    private String tablename = "Business_has_Barter";//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:mysql://localhost:3306/barter";     private static final String NAME = "root";     private static final String PASS = "root";     private static final String DRIVER ="com.mysql.jdbc.Driver";    /*     * 构造函数     */    public GenEntity(){        //创建连接        Connection con;        //查要生成实体类的表        String sql = "select * from " + tablename;        PreparedStatement pStemt = null;        try {            try {                Class.forName(DRIVER);            } catch (ClassNotFoundException e1) {                // TODO Auto-generated catch block                e1.printStackTrace();            }            con = DriverManager.getConnection(URL,NAME,PASS);            pStemt = con.prepareStatement(sql);            ResultSetMetaData rsmd = pStemt.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("datetime")){                    f_util = true;                }                if(colTypes[i].equalsIgnoreCase("image") || colTypes[i].equalsIgnoreCase("text")){                    f_sql = true;                }                colSizes[i] = rsmd.getColumnDisplaySize(i + 1);            }            String content = parse(colnames,colTypes,colSizes);            try {                File directory = new File("");                //System.out.println("绝对路径："+directory.getAbsolutePath());                //System.out.println("相对路径："+directory.getCanonicalPath());                String path=this.getClass().getResource("").getPath();                System.out.println(path);                System.out.println("src/?/"+path.substring(path.lastIndexOf("/com/", path.length())) );                FileWriter fw = new FileWriter(directory.getAbsolutePath()+ "/src/"+path.substring(path.lastIndexOf("/com/", path.length()), path.length()) + initcap(tablename) + ".java");                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();        //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("package com.share.barter.tool;\\r\\n");        sb.append("\\r\\n");        //注释部分        sb.append("   /**\\r\\n");        sb.append("    * "+tablename+" 实体类\\r\\n");        sb.append("    * "+new Date()+"  Ze Ming\\r\\n");        sb.append("    */ \\r\\n");        //实体部分        sb.append("\\r\\n\\r\\npublic class " + initcap(tablename) + "{\\r\\n");        processAllAttrs(sb);//属性        processAllMethod(sb);//get set方法        sb.append("}\\r\\n");        //System.out.println(sb.toString());        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] + ";\\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++) {            sb.append("\\tpublic void set" + initcap(colnames[i]) + "(" + sqlType2JavaType(colTypes[i]) + " " +                     colnames[i] + "){\\r\\n");            sb.append("\\tthis." + colnames[i] + "=" + colnames[i] + ";\\r\\n");            sb.append("\\t}\\r\\n");            sb.append("\\tpublic " + sqlType2JavaType(colTypes[i]) + " get" + initcap(colnames[i]) + "(){\\r\\n");            sb.append("\\t\\treturn " + colnames[i] + ";\\r\\n");            sb.append("\\t}\\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     * @param sqlType     * @return     */    private String sqlType2JavaType(String sqlType) {        if(sqlType.equalsIgnoreCase("bit")){            return "boolean";        }else if(sqlType.equalsIgnoreCase("tinyint")){            return "byte";        }else if(sqlType.equalsIgnoreCase("smallint")){            return "short";        }else if(sqlType.equalsIgnoreCase("int")){            return "int";        }else if(sqlType.equalsIgnoreCase("bigint")){            return "long";        }else if(sqlType.equalsIgnoreCase("float")){            return "float";        }else if(sqlType.equalsIgnoreCase("decimal") || sqlType.equalsIgnoreCase("numeric")                 || sqlType.equalsIgnoreCase("real") || sqlType.equalsIgnoreCase("money")                 || sqlType.equalsIgnoreCase("smallmoney")){            return "double";        }else if(sqlType.equalsIgnoreCase("varchar") || sqlType.equalsIgnoreCase("char")                 || sqlType.equalsIgnoreCase("nvarchar") || sqlType.equalsIgnoreCase("nchar")                 || sqlType.equalsIgnoreCase("text")){            return "String";        }else if(sqlType.equalsIgnoreCase("datetime")){            return "Date";        }else if(sqlType.equalsIgnoreCase("image")){            return "Blod";        }        return null;    }    /**     * 出口     * TODO     * @param args     */    public static void main(String[] args) {        new GenEntity();    }}//该片段来自于http://byrx.net