package sort;
import java.lang.reflect.Method;
import java.text.Collator;
import java.util.Comparator;
import java.util.Date;/*** @Title: LocalComparator.java* @Package* @Description: TODO(用一句话描述该文件做什么)* @author licy* @date 2018年11月8日* @version V1.0*/public class LocalComparator implements Comparator{private Comparator cmp = Collator.getInstance(java.util.Locale.CHINA);/*** 排序字段**/private String[] sortBy;/** 字段对应排序类型 (1:升序，-1：降序) 一一对应*/private int[] order;public LocalComparator(String[] sortBy, int[] order) {this.sortBy = sortBy;this.order = order;}/** 定义排序规则 如果按照不止一个属性进行排序 这按照属性的顺序进行排序,类似sql order by 即只要比较出同位置的属性就停止*/public int compare(Object o1, Object o2) {for (int i = 0; i < sortBy.length; i++) {Object value1 = getFieldValueByName(sortBy[i], o1);Object value2 = getFieldValueByName(sortBy[i], o2);if (value1 instanceof Integer && value2 instanceof Integer) {int v1 = Integer.parseInt(value1.toString());int v2 = Integer.parseInt(value2.toString());if (v1 > v2) {return 1 * this.order[i];} else if (v1 < v2) {return -1 * this.order[i];}} else if (value1 instanceof Long && value2 instanceof Long) {Long v1 = (Long) value1;Long v2 = (Long) value2;if (v1 > v2) {return 1 * this.order[i];} else if (v1 < v2) {return -1 * this.order[i];}} else if (value1.getClass() == Date.class && value2.getClass() == Date.class) {Date time1 = (Date) value1;Date time2 = (Date) value2;if (time1.getTime() > time2.getTime()) {return 1 * this.order[i];} else if (time1.getTime() < time2.getTime()) {return -1 * this.order[i];}} else {int result = cmp.compare(value1, value2);if (result != 0) {return result * this.order[i];}}}return 1;}/*** * 通过反射，获取属性值* * @param fieldName* @param o* @return*/private Object getFieldValueByName(String fieldName, Object o) {try {String firstLetter = fieldName.substring(0, 1).toUpperCase();String getter = "get" + firstLetter + fieldName.substring(1);Method method = o.getClass().getMethod(getter, new Class[] {});Object value = method.invoke(o, new Object[] {});return value;} catch (Exception e) {System.out.println("属性不存在");return null;}}
}

package sort.test;/*** @Title: Persion.java* @Package sort.test* @Description: TODO(用一句话描述该文件做什么)* @author licy* @date 2018年11月8日* @version V1.0*/public class Persion {private String name;private int age;public String getName() {return name;}public void setName(String name) {this.name = name;}public int getAge() {return age;}public void setAge(int age) {this.age = age;}public Persion() {super();// TODO Auto-generated constructor stub}public Persion(String name, int age) {super();this.name = name;this.age = age;}}

package sort.test;import java.util.ArrayList;
import java.util.Collections;
import java.util.List;import org.junit.Test;import sort.LocalComparator;public class ComparatorTest {@SuppressWarnings("unchecked")@Testpublic void test() {List list = new ArrayList();Persion p1 = new Persion("a", 3);Persion p2 = new Persion("b", 2);Persion p3 = new Persion("b", 1);list.add(p1);list.add(p2);list.add(p3);String[] sortBy = new String[] { "name", "age" };int[] order = new int[] { 1, -1 };LocalComparator lc = new LocalComparator(sortBy, order);Collections.sort(list, lc);for(int i=0;i<list.size();i++) {Persion p = (Persion) list.get(i);System.out.println(p.getName() + ":" + p.getAge());}}}