package com.xrime.innerloop.method;

import java.util.ArrayList;

import java.util.List;

/**

* 分組算法

* @author innerloop

*

*/

public class GroupByMethod {

//計算

public static List comput(List voList){

List result = new ArrayList();

//思路 第一步 獲取班級列表，第二步驟 便利 獲取班級學生列表

//第一步 獲取班級列表

List tempClassList = new ArrayList();

if(voList!=null&&voList.size()>0){

for(int i=0;i

Vo temp = voList.get(i);

if(!GroupByMethod.isClassExit(temp, tempClassList)){

ScClass sc = new ScClass();

sc.setClassId(temp.getClassId());

sc.setClassName(temp.getClassName());

tempClassList.add(sc);

}

}

}

//第二步驟 便利 獲取班級學生列表

if(tempClassList!=null&&tempClassList.size()>0){

for(int i=0;i

ScClass temp = tempClassList.get(i);

List tempStuList = new ArrayList();

for(int k=0;k

Vo cotemp = voList.get(k);

if(temp.getClassId().equals(cotemp.getClassId())){//合并

ScStudent stu = new ScStudent();

stu.setStuId(cotemp.getStuId());

stu.setStuName(cotemp.getStuName());

tempStuList.add(stu);

}

}

temp.setStuList(tempStuList);

//設置到整體返回結果中 此處后續可以擴展

result.add(temp);

temp = null;

}

}

//gc

tempClassList = null;

return result;

}

public static boolean isClassExit(Vo vo, List classList){

boolean result = false;

if(classList!=null&&classList.size()>0){

for(int i=0;i

ScClass temp = classList.get(i);

if(vo.getClassId().equals(temp.getClassId())){//已經存在,退出 不再判斷

result = true;

break;

}

}

}

return result;

}

public static List getTestData(){

Vo vo1 = new Vo("1","1班","1","小明");

Vo vo2 = new Vo("1","1班","2","小王");

Vo vo3 = new Vo("2","2班","1","小孫");

Vo vo4 = new Vo("2","2班","2","小李");

List voList = new ArrayList();

voList.add(vo1);

voList.add(vo2);

voList.add(vo3);

voList.add(vo4);

return voList;

}

public static void main(String[] args) {

List result = GroupByMethod.comput(GroupByMethod.getTestData());

for(int i=0;i

ScClass temp = result.get(i);

//System.out.println(temp.toString());

}

}

}

//中間

class Vo{

private String classId;

private String className;

private String stuId;

private String stuName;

public Vo(String classId,String className,String stuId,String stuName){

this.classId = classId;

this.className = className;

this.stuId = stuId;

this.stuName = stuName;

}

public String getClassId() {

return classId;

}

public void setClassId(String classId) {

this.classId = classId;

}

public String getClassName() {

return className;

}

public void setClassName(String className) {

this.className = className;

}

public String getStuId() {

return stuId;

}

public void setStuId(String stuId) {

this.stuId = stuId;

}

public String getStuName() {

return stuName;

}

public void setStuName(String stuName) {

this.stuName = stuName;

}

}

//班級

class ScClass{

private String className;

private String classId;

private List stuList = new ArrayList();

public String toString(){

return "班級ID"+this.classId+",班級名稱:"+this.className+"學生數量:"+this.stuList.size()+"||";

}

public String getClassName() {

return className;

}

public void setClassName(String className) {

this.className = className;

}

public String getClassId() {

return classId;

}

public void setClassId(String classId) {

this.classId = classId;

}

public List getStuList() {

return stuList;

}

public void setStuList(List stuList) {

this.stuList = stuList;

}

}

//學生

class ScStudent{

private String stuName;

private String stuId;

public String getStuName() {

return stuName;

}

public void setStuName(String stuName) {

this.stuName = stuName;

}

public String getStuId() {

return stuId;

}

public void setStuId(String stuId) {

this.stuId = stuId;

}

}

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