几个常用的公共类

返回结果的类ResultMessage

　　

package com.puyun;

import org.springframework.util.StringUtils;

public class ResultMessage {
    public static final String SUCCESS_CODE = "200";
    public static final String ERROR_CODE = "500";

    private String code;
    private String error;
    private Object result;

    public ResultMessage() {

    }

    public ResultMessage(String code, String error, Object result) {
        this.code = code;
        this.error = error;
        this.result = result;
    }


    /**
     * 返回成功的结果信息
     *
     * @param msg
     * @param result
     * @return
     */
    public static ResultMessage success(String msg, Object result) {
        if(StringUtils.isEmpty(msg)){
            msg="操作成功";
        }
        return new ResultMessage(SUCCESS_CODE, msg, result);
    }

    /**
     * 返回错误的结果信息
     *
     * @param msg
     * @param result
     * @return
     */
    public static ResultMessage error(String msg, Object result) {
        if(StringUtils.isEmpty(msg)){
            msg="操作失败";
        }
        return new ResultMessage(ERROR_CODE, msg, result);
    }

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public String getError() {
        return error;
    }

    public void setError(String error) {
        this.error = error;
    }

    public Object getResult() {
        return result;
    }

    public void setResult(Object result) {
        this.result = result;
    }
}

随机数的类

package com.puyun.common.util;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.Random;
import java.util.UUID;

/**
 * Created by huangjianbo on 2017/6/6 0006.
 */
public class RandomUtils {
    private static char[] numbersAndLetters = ("0123456789").toCharArray();
    /**
     * 不重复的订单号
     * @return
     */
    public static String getOrderIdByUUId() {
        DateFormat dateFormat = new SimpleDateFormat("yyyyMMddHHmmss");
        int first = new Random(10).nextInt(8) + 1;
        int hashCodeV = UUID.randomUUID().toString().hashCode();
        if (hashCodeV < 0) {//有可能是负数
            hashCodeV = -hashCodeV;
        }
        // 0 代表前面补充0
        // 4 代表长度为4
        // d 代表参数为正数型
        String result = dateFormat.format(new Date()) + first + String.format("%015d", hashCodeV);
        return result;
    }


    /**
     * 生成 字母+数组的随机数
     *
     * @param length
     *
     * @return
     */
    public static String randomStringValue(int length) {
        Random randGen = new Random();
        if (length < 1) {
            return null;
        }
        char[] randBuffer = new char[length];
        for (int i = 0; i < randBuffer.length; i++) {
            randBuffer[i] = numbersAndLetters[randGen.nextInt(10)];
        }
        return new String(randBuffer);
    }
    /**
     * 获取指定时间的那天 23:59:59.999 的时间
     *
     * @param date
     * @return
     */
    public static Date dayEnd(final Date date) {
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        c.set(Calendar.HOUR_OF_DAY, 23);
        c.set(Calendar.MINUTE, 59);
        c.set(Calendar.SECOND, 59);
        c.set(Calendar.MILLISECOND, 999);
        return c.getTime();
    }
}

 BaseService接口

package com.puyun.common.service;


import java.util.List;

public interface BaseService<T> {
    /**
     * &#x65b0;&#x589e;
     *
     * @param po
     * @return
     */
    public T insert(T po);

    /**
     * 查询单一数据
     *
     * @param id
     * @return
     */
    public T get(int id);

    /**
     * 查询所有数据
     *
     * @return
     */
    public List<T> queryAll();

    /**
     * 删除单一数据
     *
     * @param id
     */
    public void delete(int id);

    /**
     * 更新对象
     *
     * @param po
     */
    public void update(T po);

}