List排序共通代码

Posted 2020-10-13 霄九天

此共通方法可以根据特定字段进行排序

package com.gomecar.index.common.utils;

import java.lang.reflect.Method;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

/**
 * 对List中数据根据某个字段进行排序
 * Created by xiaotian on 2017/3/20.
 */
public class ListSortUtil<T> {
    /**
     * @param targetList 目标排序List
     * @param sortField 排序字段(实体类属性名)
     * @param sortMode 排序方式（asc or  desc）
     */
    @SuppressWarnings({ "unchecked", "rawtypes" })
    public   void sort(List<T> targetList, final String sortField, final String sortMode) {

        Collections.sort(targetList, new Comparator() {
            public int compare(Object obj1, Object obj2) {
                int retVal = 0;
                try {
                    //首字母转大写
                    String newStr=sortField.substring(0, 1).toUpperCase()+sortField.replaceFirst("\\w","");
                    String methodStr="get"+newStr;

                    Method method1 = ((T)obj1).getClass().getMethod(methodStr, null);
                    Method method2 = ((T)obj2).getClass().getMethod(methodStr, null);
                    if (sortMode != null && "desc".equals(sortMode)) {
                        retVal = method2.invoke(((T) obj2), null).toString().compareTo(method1.invoke(((T) obj1), null).toString()); // 倒序
                    } else {
                        retVal = method1.invoke(((T) obj1), null).toString().compareTo(method2.invoke(((T) obj2), null).toString()); // 正序
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                    //throw new RuntimeException();
                }
                return retVal;
            }
        });
    }
}