JAVA 对象数组按照多个属性进行排序
下文可以直接拿来运行使用，也可以直接下载附件包，编译直接运行就可以看到效果。
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//ObjectSort
package sort;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
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public class ObjectSort {
??? /**
???? * @param args
???? */
??? public static void main(String[] args) {
??????? /**
???????? *
???????? * purpose： 根据对象的某个或者某些属性排序
???????? * Java里面包含8个基本数据类型，分别是：boolean、byte、char、short、int、float、douboe、long
???????? * 只比较非boolean和byte类型的属性，和大多数运用环境适应，如果有特殊要求，请自己修改。
???????? * 使用时只要将对象属性列表和需要排序的List传入即可
???????? * **/
??????? List arrayDemo = new ArrayList();
??????
??????? Person p1 = new Person();
??????? p1.setName("zhang san");
??????? p1.setAge(22);
??????? p1.setSalary(160);
??????
??????? Person p2 = new Person();
??????? p2.setName("zhang san");
??????? p2.setAge(22);
??????? p2.setSalary(150);
??????
??????? Person p3 = new Person();
??????? p3.setName("zhang san");
??????? p3.setAge(25);
??????? p3.setSalary(1900);
??????
??????? Person p4 = new Person();
??????? p4.setName("zhao liu");
??????? p4.setAge(25);
??????? p4.setSalary(3000);
??????
??????? Person p5 = new Person();
??????? p5.setName("liu qi");
??????? p5.setAge(30);
??????? p5.setSalary(2000);
??????
??????? arrayDemo.add(p1);
??????? arrayDemo.add(p2);
??????? arrayDemo.add(p3);
??????? arrayDemo.add(p4);
??????? arrayDemo.add(p5);
??????
??????? //*********开始比较********//
??????? CommonComparator comparator = new CommonComparator();
??????? System.out.println("1.sort by name, age and salary");
??????? comparator.setFields_user(new String[]{"name","age","salary"});
??????? Collections.sort(arrayDemo, comparator);
??????? for(int i=0;i<arrayDemo.size();i++)
??????? {
??????????? Person person = (Person)arrayDemo.get(i);
??????????? System.out.println("name:"+person.getName()+" age:"+person.getAge()+" salary:"+person.getSalary());
??????? }
???????
??????? System.out.println("1.sort by name, age");
??????? comparator.setFields_user(new String[]{"name","age"});
??????? Collections.sort(arrayDemo, comparator);
??????? for(int i=0;i<arrayDemo.size();i++)
??????? {
??????????? Person person = (Person)arrayDemo.get(i);
??????????? System.out.println("name:"+person.getName()+" age:"+person.getAge()+" salary:"+person.getSalary());
??????? }
??? }
}
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//CommonComparator
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package sort;
import java.lang.reflect.Method;
import java.math.BigDecimal;
import java.text.CollationKey;
import java.text.Collator;
import java.util.Comparator;
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public class CommonComparator implements Comparator {
??? /***
???? * @param
???? * 比较对象的属性用String[]的形式传过来
???? * 比较的对象一定要符合javaBean，即要有Set,Get方法
???? * */
??? String[] fields_user = null;
??
??
??? public String[] getFields_user() {
??????? return fields_user;
??? }
??? public void setFields_user(String[] fields_user) {
??????? this.fields_user = fields_user;
??? }
??? /**
???? * 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,类是sql order by
???? * 即只要比较出同位置的属性就停止
???? * */
??? public int compare(Object obj1, Object obj2)
??? {
??????? //没有属性，则不排序
??????? if(fields_user == null || fields_user.length<=0)
??????? {
??????????? return 2;//不比较
??????? }
??????? for(int i=0;i<fields_user.length;i++)
??????? {
??????????? //return compareField(obj1,obj2,fields_user[i]);
??????????? if(compareField(obj1,obj2,fields_user[i])>0)
??????????? {//如果obj1的属性值大于obj2的属性值，则返回正数
??????????????? return 1;
???????????? }else if(compareField(obj1,obj2,fields_user[i])<0){
???????????????? return -1;
???????????? }
??????? }
??????? return 0;
??? }
??? /**
???? * @param fieldName
???? * 根据属性名排序
???? * */
??? private static int compareField(Object o1,Object o2,String fieldName)
??? {
??????????? try
??????????? {
??????????????? Object value1 = getFieldValueByName(fieldName,o1);
??????????????? Object value2 = getFieldValueByName(fieldName,o2);
?????????????
??????????????? //--字符串比较
??????????????? if(value1 instanceof String)
??????????????? {
????????????????? String v1 = getFieldValueByName(fieldName,o1).toString();
????????????????? String v2 = getFieldValueByName(fieldName,o2).toString();
??????????????????? Collator myCollator = Collator.getInstance();
??????????????????? CollationKey[] keys = new CollationKey[5];
??????????????????? keys[0] = myCollator.getCollationKey(v1);
??????????????????? keys[1] = myCollator.getCollationKey(v2);
??????????????????? return (keys[0].compareTo(keys[1]));
??????????????? }
??????????????? //--非比较属性不比较
??????????????? else if("java.lang.Boolean".equals(value1.getClass().getName()) || "java.lang.Byte".equals(value1.getClass().getName()))
??????????????? {
??????????????????? return 0;
??????????????? }else
??????????????? {
??????????????????? BigDecimal b1 = new BigDecimal(value1.toString());
??????????????????? BigDecimal b2 = new BigDecimal(value2.toString());
??????????????????? return b1.compareTo(b2);
??????????????? }
??????????? } catch (Exception e)
??????????? {
??????????????? System.out.println("-----------------------------------------");
??????????????? System.out.println("---------对象的该属性不存在或者不允许在此安全级别上反射该属性，详情请查阅JAVA DOC--------");
??????????????? System.out.println("-----------------------------------------");
??????????????? e.printStackTrace();
??????????? }
??????????? //小于
??????????? return -1;
??? }
??? /**
???? * @param
???? * fieldName 属性名
???? * obj 对象
???? * 反射获得该属性的值
???? * */
??? private static Object getFieldValueByName(String fieldName,Object obj)
??? {
??????? try
??????? {
??????????? String Letter = fieldName.substring(0,1).toUpperCase();
??????????? String methodStr = "get"+Letter+fieldName.substring(1);
??????????? Method method = obj.getClass().getMethod(methodStr, new Class[]{});
??
??????????? Object value = method.invoke(obj, new Object[]{});
???????????
??????????? return value;
??????? }catch(Exception e)
??????? {
??????????? System.out.println("------------------------------------------------------");
??????????? System.out.println("---------该"+fieldName+"属性不存在----------------------");
??????????? System.out.println("------------------------------------------------------");
??????????? return null;
??????? }
??? }
}
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//Person
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package sort;
public class Person {
??? public Person(){}
???
??? private String name;
??? private int age;
??? private long salary;
??
??? public long getSalary() {
??????? return salary;
??? }
??? public void setSalary(long salary) {
??????? this.salary = salary;
??? }
??? public int getAge() {
??????? return age;
??? }
??? public void setAge(int age) {
??????? this.age = age;
??? }
??? public String getName() {
??????? return name;
??? }
??? public void setName(String name) {
??????? this.name = name;
??? }
}
