package com.longlonggo.myTest; import java.util.ArrayList; import java.util.List; //测试类主方法 public class MyTest { public static void main(String[] args) { List<UserEntity> list = new ArrayList<UserEntity>(); UserEntity u1 = new UserEntity(); u1.setId(1); u1.setName("A"); u1.setQuantity(1); UserEntity u2 = new UserEntity(); u2.setId(1); u2.setName("B"); u2.setQuantity(2); UserEntity u3 = new UserEntity(); u3.setId(1); u3.setName("A"); u3.setQuantity(3); list.add(u1); list.add(u2); list.add(u3); List<UserEntity> resultList = new ArrayList<UserEntity>(); for (UserEntity _o : list) { boolean isFind = false; for(int i=0;i<resultList.size();i++){ if(_o.getName().equals(resultList.get(i).getName())){ isFind = true; resultList.get(i).setQuantity(resultList.get(i).getQuantity() + _o.getQuantity()); } } if(!isFind){ resultList.add(_o); } } for (UserEntity _r : resultList) { System.out.println(_r.getName()+","+_r.getQuantity()); } } }
package com.longlonggo.myTest; //实体属性 public class UserEntity { private int id; private String name; private int quantity; public int getId() { return id; } public String getName() { return name; } public int getQuantity() { return quantity; } public void setId(int id) { this.id = id; } public void setName(String name) { this.name = name; } public void setQuantity(int quantity) { this.quantity = quantity; } }