使用多个属性对对象列表进行分组

如何使用Java中的多个属性对对象列表进行分组？如果我有State code，Dept，Branch，Amount，Account的财务详细信息列表。现在我想要添加相同的数量state code，Dept，Branch，Amount,AccountCode。使用多个属性对对象列表进行分组

FinancialDetails f1 = new FinancialDetails("01","005","test1",12.23D,"12345"); 
    FinancialDetails f2 = new FinancialDetails("01","005","test1",123.23D,"12345"); 
    FinancialDetails f3 = new FinancialDetails("01","005","test1",99.23D,"12345"); 
    FinancialDetails f4 = new FinancialDetails("02","006","test1",123.23D,"89898"); 
    FinancialDetails f5 = new FinancialDetails("02","006","test1",125.23D,"89898"); 
    FinancialDetails f6 = new FinancialDetails("03","020","test2",625.23D,"89898"); 
    List<FinancialDetails> list = new ArrayList<FinancialDetails>(); 
    list.add(f1); 
    list.add(f2); 
    list.add(f3); 
    list.add(f4); 
    list.add(f5); 
    list.add(f6);

现在我想用相同的statecode，部门，分公司添加量来创建一个对象，账户

来源

2014-07-22 user1166528

让我们了解您已经尝试并描述您遇到任何错误。 –

我没有得到任何异常。我试图分组，以相同的国家代码，分支，帐户和对象创建作为对象通过添加金额 – user1166528

如果您尝试请包括您尝试过的代码。 –

尝试：

private static class Key { 
    String stateCode; 
    String dept; 
    // ... 
    // + hashcode equals 
} 
public Collection<List<FinancialDetails>> group(List<FinancialDetails> original) { 
    Map<Key, List<FinancialDetails>> groupingMap = new HashMap<>(); 
    for(FinancialDetails fd : original) { 
     Key key = new Key(fd.getStateCode, fd.getDept); // ... 
     List<FinancialDetails> group = groupingMap.get(key); 
     if(group == null) { 
      group = new ArrayList<>(); 
      groupingMap.put(key, group); 
     } 
     group.add(fd); 
    } 
    return groupingMap.values(); 
}

来源

2014-07-22 12:55:07

类学生{

private String age; 
private String name; 
public String getAge() { 
    return age; 
} 
public void setAge(String age) { 
    this.age = age; 
} 
@Override 
public String toString() { 
    return "Student [age=" + age + ", name=" + name + "]"; 
} 
public String getName() { 
    return name; 
} 
public void setName(String name) { 
    this.name = name; 
} 
public Student(String age, String name) { 
    super(); 
    this.age = age; 
    this.name = name; 
}

}

publi C类你好{

public static void main(String args[]){ 

    ArrayList<Student> al=new ArrayList<Student>(); 
    al.add(new Student("12","Prince")); 
    al.add(new Student("10", "Amar")); 
    al.add(new Student("12","Akansha")); 
    HashMap<String, List<Student>> map=new HashMap<String, List<Student>>(); 
    Iterator<Student> itr=al.iterator(); 
    while(itr.hasNext()){ 

     Student s1=itr.next(); 
     if(map.containsKey(s1.getAge())){ 

      List<Student> innerList=map.get(s1.getAge()); 
      innerList.add(s1); 
      map.put(s1.getAge(), innerList); 

     }else{ 

      List<Student> innerList=new ArrayList<Student>(); 
      innerList.add(s1); 
      map.put(s1.getAge(),innerList); 

     } 
    } 

    for(Map.Entry<String, List<Student>> entry:map.entrySet()){ 

     String key=entry.getKey(); 
     List<Student> list=entry.getValue(); 
     System.out.print(key+"="); 
     for(Student obj:list){ 

      System.out.print(obj+" "); 
     } 
     System.out.println(); 
    } 


}

}

来源

2016-02-22 05:30:06 Prince

使用多个属性对对象列表进行分组

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