JAVA实现存在更新不存在插入与及多余的进行删除(二)

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依赖于mybatis-plus

一共一个接口两个类。下面直接上代码，后续再作陈述

1、接口：

package com.service.biz;

import java.util.List;

/**
 * 根据入参与数据库存在的数据，获取可以删除、插入、更新的数据
 *
 * @author sven
 * @version 1.1
 * @since 2022/7/21
 */
public interface ICudDataService {
    /**
     * 找到要删除的数据
     *
     * @param paramData
     * @param dbData
     * @param clazz
     * @return 主键id列表
     */
    List getDeleteData(List paramData, List dbData, Class clazz);

    /**
     * 找到要进行更新的数据
     *
     * @param paramData
     * @param dbData
     * @param clazz
     * @return
     */
    List getUpdateData(List paramData, List dbData, Class clazz);

    /**
     * 找到要进行插入的数据
     *
     * @param paramData
     * @param dbData
     * @param clazz
     * @return
     */
    List getInsertData(List paramData, List dbData, Class clazz);

    /**
     * 保存数据，处理数据的增删改
     *
     * @param paramData 前台的参数
     * @param dbData    后台的数据
     * @param clazz     前后台参数对应的class
     * @param beanName      spring bean服务实现类名称
     * @return  SUCCESS：操作成功
     */
    String saveData(List paramData, List dbData, Class clazz,String beanName);
}

2、接口的实现类：

package com.service.biz.impl;

import com.service.SpringBeanContext;
import com.service.biz.biz.ICudDataService;
import org.apache.commons.collections.CollectionUtils;
import org.springframework.stereotype.Service;

import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

/**
 * 根据入参与数据库存在的数据，获取可以删除、插入、更新的数据
 *
 * @author sven
 * @version 1.1
 * @since 2022/7/21
 */
@Service
public class CudDataServiceImpl implements ICudDataService {
    private static final String MAIN_METHOD = "getId";

    private static final String DELETE_METHOD = "deleteBatchIds";
    private static final String INSERT_METHOD = "insertBatch";
    private static final String UPDATE_METHOD = "updateBatchById";

    public List getDeleteData(List paramData, List dbData, Class clazz) {
        if (CollectionUtils.isEmpty(paramData) && CollectionUtils.isNotEmpty(dbData))
            return dbData.stream().map(obj -> getId(obj, clazz)).collect(Collectors.toList());
        if (CollectionUtils.isEmpty(dbData)) return new ArrayList<>();
        return dbData.stream().filter(db -> !paramData.stream().anyMatch(para -> getId(db, clazz).equals(getId(para, clazz)))).map(obj -> getId(obj, clazz)).collect(Collectors.toList());
    }

    public List getUpdateData(List paramData, List dbData, Class clazz) {
        if (CollectionUtils.isEmpty(paramData) || CollectionUtils.isEmpty(dbData)) return new ArrayList<>();
        return paramData.stream().filter(para -> dbData.stream().anyMatch(db -> getId(db, clazz).equals(getId(para, clazz)))).collect(Collectors.toList());
    }

    public List getInsertData(List paramData, List dbData, Class clazz) {
        if (CollectionUtils.isEmpty(paramData)) return new ArrayList<>();
        if (CollectionUtils.isEmpty(dbData)) return paramData;
        return paramData.stream().filter(para -> !dbData.stream().anyMatch(db -> getId(db, clazz).equals(getId(para, clazz)))).collect(Collectors.toList());
    }

    @Override
    public String saveData(List paramData, List dbData, Class clazz, String beanName) {
        try {
            List deleteData = getDeleteData(paramData, dbData, clazz);
            Object[] Paras = {deleteData};
            if (CollectionUtils.isNotEmpty(deleteData)) {
                SpringBeanContext.springInvokeMethod(beanName, DELETE_METHOD, Paras);
            }
            List insertData = getInsertData(paramData, dbData, clazz);
            Object[] insertDataParas = {insertData};
            if (CollectionUtils.isNotEmpty(insertData)) {
                SpringBeanContext.springInvokeMethod(beanName, INSERT_METHOD, insertDataParas);
            }
            List updateData = getUpdateData(paramData, dbData, clazz);
            Object[] updateDataParas = {updateData};
            if (CollectionUtils.isNotEmpty(updateData)) {
                SpringBeanContext.springInvokeMethod(beanName, UPDATE_METHOD, updateDataParas);
            }
        } catch (Exception e) {
            e.printStackTrace();
            return "FAIL:" + e.getMessage();
        }
        return "SUCCESS";
    }

    private String getId(T t, Class clazz) {
        try {
            Method getId = clazz.getMethod(MAIN_METHOD);
            return (String) getId.invoke(t, null);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "";
    }
}

3、一个动态调用bean的类

package com.service;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;
import org.springframework.util.ReflectionUtils;

import java.lang.reflect.Method;
import java.util.Collection;
import java.util.List;

/**
 * @author sven
 * @version 1.0
 * @since 2022/7/26
 */
@Component
public class SpringBeanContext implements ApplicationContextAware {
    private static final Logger log = LoggerFactory.getLogger(SpringBeanContext.class);
    protected static ApplicationContext applicationContext;

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        SpringBeanContext.applicationContext = applicationContext;
    }

    public static Object getBean(String beanName) {
        if (applicationContext == null) {
            log.error("未初始化Spring上下文");
            return null;
        } else if (!applicationContext.containsBean(beanName)) {
            log.warn("Spring上下文中不存在要查找的对象[{}]", beanName);
            return null;
        } else {
            return applicationContext.getBean(beanName);
        }
    }

    public static  T getBean(Class clazz) {
        if (applicationContext == null) {
            log.error("未初始化Spring上下文");
            return null;
        } else {
            return applicationContext.getBean(clazz);
        }
    }

    public static  T getBean(String name, Class clazz) {
        if (applicationContext == null) {
            log.error("未初始化Spring上下文");
            return null;
        } else {
            return applicationContext.getBean(name, clazz);
        }
    }


    public static Object springInvokeMethod(String serviceName, String methodName, Object[] params) throws Exception {
        Object service = getBean(serviceName);
        Class[] paramClass = null;
        if (params != null) {
            int paramsLength = params.length;
            paramClass = new Class[paramsLength];
            for (int i = 0; i < paramsLength; i++) {
                paramClass[i] = params[i] instanceof Class ? (Class) params[i] : params[i].getClass();
            }
        }
        // 找到方法
        Method method = ReflectionUtils.findMethod(service.getClass(), methodName, paramClass);
        // 定制化写法 单独针对通用保存方法写死参数类型的获取
        if (method == null) method = ReflectionUtils.findMethod(service.getClass(), methodName, List.class);
        if (method == null) method = ReflectionUtils.findMethod(service.getClass(), methodName, Collection.class);
        // 定制化写法 end
        // 执行方法
        return ReflectionUtils.invokeMethod(method, service, params);
    }
}

大体思路是通过lambda比较入参与数据库的数据，找出需要删除、新增、修改的数据。

再反射调用bean的mybatis-plus通用方法。

诸位看官可以参考下迭代优化成一个更通用的工具。

使用体验：

       7月份完成的代码，到现在也实际在项目中用了一个多月，已在生产应用中应用！只要遵循好约定的入参与数据库数据用同一实体类，效果杠杠的，一下子不用去思考是否要删除或新增或修改了。

后续看情况再作迭代优化。暂时还是处于满足要求的状况