根据库表结构自动生成java实体类(生成规范的变量及get/set方法).

/** * java根据库表结构自动生成java实体,在网上找了相关资料，已经有很多大侠实现了这功能。 * 但是并没有一个使我自己满意的，要么生成的变量不规范，要么就是格式很乱。 * 所以我参照网上一些已有的方法，自己动手改进了下，实现了可以生成规范的字段名及 * get/set方法，只不过这里有个前提，就是在新建表字段时如果字段名较长，那么必须遵守用"_"隔开。 * 其实只有这样才能规范，毕竟电脑也不是万能的，不可能根据你想要的格式自动生成规范的变量名及get/set方法。 */ 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.user.entity";//指定实体生成所在包的路径 private String authorName = "张三";//作者名字 private String tablename = "RECORD";//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:@192.168.1.113:1521:eport";  private static final String NAME = "test";  private static final String PASS = "test";  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 {    Class.forName(DRIVER);   } catch (ClassNotFoundException e1) {    // TODO Auto-generated catch block    e1.printStackTrace();   }      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("");    //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())) );//    String outputPath = directory.getAbsolutePath()+ "/src/"+path.substring(path.lastIndexOf("/com/", path.length()), path.length()) + initcap(tablename) + ".java";    String outputPath = directory.getAbsolutePath()+ "/src/"+this.packageOutPath.replace(".", "/")+"/"+initcap(tablename) + ".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();    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("    * "+initcap(tablename)+" 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 " + initcap(tablename) + "{\r\n");  processAllAttrs(sb);//属性  processAllMethod(sb);//get set方法  sb.append("}\r\n");       //System.out.println("999999 = " +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]) + " " + defineVar(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("\n\tpublic void set" + transVar(colnames[i]) + "(" + sqlType2JavaType(colTypes[i]) + " " +     defineVar(colnames[i]) + "){\r\n");   sb.append("\t\tthis." + this.defineVar(colnames[i]) + "=" + this.defineVar(colnames[i]) + ";\r\n");   sb.append("\t}\r\n");   sb.append("\n\tpublic " + sqlType2JavaType(colTypes[i]) + " get" + transVar(colnames[i]) + "(){\r\n");   sb.append("\t\treturn " + defineVar(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.toLowerCase().toCharArray();  System.out.println("6666 str = "+str.toString());  if(ch[0] >= 'a' && ch[0] <= 'z'){   ch[0] = (char)(ch[0] - 32);  }    return new String(ch); }  /**  * 用于生成get/set方法时  * 功能：先将变量字母全变为小写，将第一个字母变为大写，将紧跟“_”后面一个字母大写，并去掉“_”.  * @param str  * @return  */ private String transVar(String str){  System.out.println("111"+str);  int index = 0;  if(str.indexOf("_")!=-1){   index = str.indexOf("_");   str = str.replace("_", "");  }  System.out.println("222"+str);  char[] ch = str.toLowerCase().toCharArray();  if(ch[0] >= 'a' && ch[0] <= 'z'){   ch[0] = (char)(ch[0] - 32);   if(index!=0){    ch[index] = (char)(ch[index] - 32);   }  }  str =  new String(ch);  System.out.println("333"+str);  return str; }  /**  * 用于定义变量名  * 功能：先将变量字母全变为小写，将紧跟“_”后面一个字母大写，并去掉“_”.  * @param str  * @return  */ private String defineVar(String str){  int index = 0;  if(str.indexOf("_")!=-1){   index = str.indexOf("_");   str = str.replace("_", "");  }  char[] ch = str.toLowerCase().toCharArray();  if(ch[0] >= 'a' && ch[0] <= 'z'&&index!=0){   ch[index] = (char)(ch[index] - 32);  }  str =  new String(ch);  return str; } /**  * 功能：获得列的数据类型  * @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();   }}