最近做系统老做一些相同的工作,就想写一自动生成代码的工具类来方便以后的开法,我从网上整理修改了一些方法感觉还不错,接下来我还陆续跟新一些自动生成代码的工具类,希望对大家有用。觉得不好轻点喷。import java.io.BufferedWriter; import java.io.File; import java.io.FileWriter; import java.io.IOException; 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.util.Vector; public class reflectBean { private Connection connection; private PreparedStatement UserQuery; /*MySQL url的连接字符串*/ private static String url = "jdbc:mysql://127.0.0.1:3306/wechat?useUnicode=true&characterEncoding=UTF-8"; //账号 private static String user = "root"; //密码 private static String passWord = "123456"; private Vector<String> vector = new Vector<String>(); //mysql jdbc的java包驱动字符串 private String driverClassName = "com.mysql.jdbc.Driver"; //数据库中的表名 String table = "orderList"; //数据库的列名称 private String[] colnames; // 列名数组 //列名类型数组 private String[] colTypes; public reflectBean(){ try {//驱动注册 Class.forName(driverClassName); if (connection == null || connection.isClosed()) //获得链接 connection = DriverManager.getConnection(url, user, password); } catch (ClassNotFoundException ex) { ex.printStackTrace(); System.out.println("Oh,not"); } catch (SQLException e) { e.printStackTrace(); System.out.println("Oh,not"); } } public Connection getConnection() { return connection; } public void setConnection(Connection connection) { this.connection = connection; } public void doAction(){ String sql = "select * from "+table; try { PreparedStatement statement = connection.prepareStatement(sql); //获取数据库的元数据 ResultSetMetaData metadata = statement.getMetaData(); //数据库的字段个数 int len = metadata.getColumnCount(); //字段名称 colnames = new String[len+1]; //字段类型 --->已经转化为java中的类名称了 colTypes = new String[len+1]; for(int i= 1;i<=len;i++){ //System.out.println(metadata.getColumnName(i)+":"+metadata.getColumnTypeName(i)+":"+sqlType2JavaType(metadata.getColumnTypeName(i).toLowerCase())+":"+metadata.getColumnDisplaySize(i)); //metadata.getColumnDisplaySize(i); colnames[i] = metadata.getColumnName(i); //获取字段名称 System.out.println(colnames[i]); colTypes[i] = sqlType2JavaType(metadata.getColumnTypeName(i)); //获取字段类型 System.out.println(metadata.getColumnTypeName(i)); System.out.println(colTypes[i]); } } catch (SQLException e) { e.printStackTrace(); } } /* * mysql的字段类型转化为java的类型*/ 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") ||sqlType.equalsIgnoreCase("date")){ return "Date"; }else if(sqlType.equalsIgnoreCase("image")){ return "Blod"; }else if(sqlType.equalsIgnoreCase("timestamp")){ return "Timestamp"; } return null; } /*获取整个类的字符串并且输出为java文件 * */ public StringBuffer getClassStr(){ //输出的类字符串 StringBuffer str = new StringBuffer(""); //获取表类型和表名的字段名 this.doAction(); //校验 if(null == colnames && null == colTypes) return null; //拼接 str.append("public class "+GetTuoFeng(table)+" {/r/n"); //拼接属性 for(int index=1; index < colnames.length ; index++){ str.append(getAttrbuteString(colnames[index],colTypes[index])); } //拼接get,Set方法 for(int index=1; index < colnames.length ; index++){ str.append(getGetMethodString(colnames[index],colTypes[index])); str.append(getSetMethodString(colnames[index],colTypes[index])); } str.append("}/r/n"); //输出到文件中 File file = new File("E:/mengwx/【源码】mysql版本_spring4.0/FHMYSQL/src/com/fh/entity/"+GetTuoFeng(table)+".java"); BufferedWriter write = null; try { write = new BufferedWriter(new FileWriter(file)); write.write(str.toString()); write.close(); } catch (IOException e) { e.printStackTrace(); if (write != null) try { write.close(); } catch (IOException e1) { e1.printStackTrace(); } } return str; } /* * 获取字段字符串*/ public StringBuffer getAttrbuteString(String name, String type) { if(!check(name,type)) { System.out.println("类中有属性或者类型为空"); return null; }; String format = String.format(" private %s %s;/n/r", new String[]{type,name}); return new StringBuffer(format); } /* * 校验name和type是否合法*/ public boolean check(String name, String type) { if("".equals(name) || name == null || name.trim().length() ==0){ return false; } if("".equals(type) || type == null || type.trim().length() ==0){ return false; } return true; } /* * 获取get方法字符串*/ private StringBuffer getGetMethodString(String name, String type) { if(!check(name,type)) { System.out.println("类中有属性或者类型为空"); return null; }; String Methodname = "get"+GetTuoFeng(name); String format = String.format(" public %s %s(){/n/r", new Object[]{type,Methodname}); format += String.format(" return this.%s;/r/n", new Object[]{name}); format += " }/r/n"; return new StringBuffer(format); } //将名称首字符大写 private String GetTuoFeng(String name) { name = name.trim(); if(name.length() > 1){ name = name.substring(0, 1).toUpperCase()+name.substring(1); }else { name = name.toUpperCase(); } return name; } /* * 获取字段的get方法字符串*/ private Object getSetMethodString(String name, String type) { if(!check(name,type)) { System.out.println("类中有属性或者类型为空"); return null; }; String Methodname = "set"+GetTuoFeng(name); String format = String.format(" public void %s(%s %s){/n/r", new Object[]{Methodname,type,name}); format += String.format(" this.%s = %s;/r/n", new Object[]{name,name}); format += " }/r/n"; return new StringBuffer(format); } public static void main(String[] args) { reflectBean bean = new reflectBean(); System.err.println(bean.getClassStr()); } }
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