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从数据库表反射出实体类,自动生成实体类

2016-10-25 10:57 393 查看
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

 * @author  Tumi

 * 日期:2012-10-10

 */

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;rn");

  }

  if(f_sql){

   sb.append("import java.sql.*;rn");

  }

  sb.append("package com.share.barter.tool;rn");

  sb.append("rn");

  //注释部分

  sb.append("   /**rn");

  sb.append("    * "+tablename+" 实体类rn");

  sb.append("    * "+new Date()+"  Ze Mingrn");

  sb.append("    */ rn");

  //实体部分

  sb.append("rnrnpublic class " + initcap(tablename) + "{rn");

  processAllAttrs(sb);//属性

  processAllMethod(sb);//get set方法

  sb.append("}rn");

  

     //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] + ";rn");

  }

  

 }

 /**

  * 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] + "){rn");

   sb.append("tthis." + colnames[i] + "=" + colnames[i] + ";rn");

   sb.append("t}rn");

   sb.append("tpublic " + sqlType2JavaType(colTypes[i]) + " get" + initcap(colnames[i]) + "(){rn");

   sb.append("ttreturn " + colnames[i] + ";rn");

   sb.append("t}rn");

  }

  

 }

 

 /**

  * 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();

  

 }

}

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
* @author Tumi
* 日期:2012-10-10
*/
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;rn");
}
if(f_sql){
sb.append("import java.sql.*;rn");
}
sb.append("package com.share.barter.tool;rn");
sb.append("rn");
//注释部分
sb.append("/**rn");
sb.append("*"+tablename+"实体类rn");
sb.append("*"+new Date()+"Ze Mingrn");
sb.append("*/ rn");
//实体部分
sb.append("rnrnpublic class"+ initcap(tablename) +"{rn");
processAllAttrs(sb);//属性
processAllMethod(sb);//get set方法
sb.append("}rn");

//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] +";rn");
}

}

/**
* 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] +"){rn");
sb.append("tthis."+ colnames[i] +"="+ colnames[i] +";rn");
sb.append("t}rn");
sb.append("tpublic"+ sqlType2JavaType(colTypes[i]) +"get"+ initcap(colnames[i]) +"(){rn");
sb.append("ttreturn"+ colnames[i] +";rn");
sb.append("t}rn");
}

}

/**
* 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();

}

}
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