Java自动生成insert,update语句_JAVA_编程开发_程序员俱乐部

class="java">

public class User {
	private String id;
	private String username;
	private String password;
	public String getUsername() {
		return username;
	}
	
	/**
	 * getter,setter.....
	 */
	
}

public class GenerateSql_Util {
	public static String getSqlInset(Object obj) {
		try {
			Class<? extends Object> c = obj.getClass();
			Field[] fields = c.getDeclaredFields();
			String tableName = c.getSimpleName();
			StringBuffer sbValue = new StringBuffer();
			StringBuffer sbField = new StringBuffer();
			sbField.append("INSERT INTO " + tableName.toLowerCase() + "(");
			int fieldLength = fields.length;
			for(int i=0;i<fieldLength;i++){
				fields[i].setAccessible(true);
				sbField.append(fields[i].getName().toLowerCase()+',');
				sbValue.append("'"+fields[i].get(obj).toString() +"',");
			}
			return sbField.replace(sbField.length()-1, sbField.length(), ") VALUES(").append(sbValue.replace(sbValue.length()-1, sbValue.length(), ");")).toString();
		} catch (IllegalAccessException e1) {
			e1.printStackTrace();
		}
		return null;
	}
	
	public static String getSqlUpdate(Object obj) {
		try {
			Field[] fields = obj.getClass().getDeclaredFields();
			String tableName = obj.getClass().getSimpleName();
			StringBuffer sb = new StringBuffer();
			sb.append("UPDATE "+ tableName.toLowerCase() +" SET ");
			int fieldLength = fields.length;
			for(int i=0;i<fieldLength;i++){
				fields[i].setAccessible(true);
				sb.append(fields[i].getName() + " = '" + fields[i].get(obj) +"',");
			}
			return sb.replace(sb.length()-1, sb.length(), " ").toString();
		} catch (IllegalAccessException e1) {
			e1.printStackTrace();
		}
		return null;
	}
}

public class test {

	public static void main(String[] args) {
		User u = new User();
		u.setId("1");
		u.setUsername("u1");
		u.setPassword("p1");
		System.out.println(GenerateSql_Util.getSqlInset(u));
		String updateSql = GenerateSql_Util.getSqlUpdate(u) + " WHERE id = '"+ u.getId()+"';";
		System.out.println(updateSql);
	}
}