Question

我有一个类似下面的hashmap：

someMap= new HashMap<Integer, String>();
someMap.put(1, "variable1");
someMap.put(2, "variable2");
someMap.put(3, "variable3");
someMap.put(4, "variable4");
someMap.put(5, "variable5");

我有一个类似下面的java类：

public class SomeVO {

      Long someNumber;
      String  shortDesc;

    public Long getSomeNumber() {
        return someNumber;
    }
    public void setSomeNumber(Long someNumber) {
        this.someNumber = someNumber;
    }

    public String getShortDesc() {
        return shortDesc;
    }
    public void setShortDesc(String shortDesc) {
        this.shortDesc = shortDesc;
    }

}

在数据库中我有像

这样的值

someNumber and short-description

当我查询数据库时，我返回一个列表，其中包含上述信息：

List<SomeVO > existingSomeNumberAndShortDescriptionList

现在我必须将List与someMap进行比较，然后返回两个地图，这些地图将变量作为该变量的键和简短描述。

就像我必须从existingSomeNumberAndShortDescriptionList进行比较，我需要得到像

这样的最终结果

variable1，shortDescription（来自existingSomeNumberAndShortDescriptionList中可用的数据库），

和变量1，Y或N，如果某个号码在列表中可用，则为Y其他N

Answer 1

您的代码将是这样的：

public class Test {

/**
 * @param args
 */
public static void main(String[] args) {


    // Loaded Hashmap-------------------------------------------------------------------

    HashMap<Long, String> someMap= new HashMap<Long, String>();
    someMap.put(1L, "variable1");
    someMap.put(2L, "variable2");
    someMap.put(3L, "variable3");
    someMap.put(4L, "variable4");
    someMap.put(5L, "variable5");


    // List getting from db-------------------------------------------------------------------

    List<SomeVO> existingSomeNumberAndShortDescriptionList  = new ArrayList<SomeVO>();

    SomeVO someVO1=new SomeVO();
    someVO1.setSomeNumber(1L);
    someVO1.setShortDesc("Description 1");

    SomeVO someVO2=new SomeVO();
    someVO2.setSomeNumber(2L);
    someVO2.setShortDesc("Description 2");

    existingSomeNumberAndShortDescriptionList.add(someVO1);
    existingSomeNumberAndShortDescriptionList.add(someVO2);

    //--------------------------------------------------------------------------------------------


    HashMap<String, String> hashmap1 =new HashMap<String, String>();
    HashMap<Long, String> hashmap2 =new HashMap<Long, String>();

    //Iterate through list of bean
    for (Iterator<SomeVO> iterator = existingSomeNumberAndShortDescriptionList .iterator(); iterator.hasNext();) {
        SomeVO someVO = (SomeVO) iterator.next();

        // Compare key with main hashmap and Put in hashmap 1
        hashmap1.put(someMap.get(someVO.getSomeNumber()),someVO.getShortDesc());

        // Compare key with main hashmap and check if number exists and Put in hashmap 2
        if(someMap.containsKey(someVO.getSomeNumber()))
            hashmap2.put(someVO.getSomeNumber(),"Y");
        else
            hashmap2.put(someVO.getSomeNumber(),"N");
    }


    // print hashmaps
    System.out.println(hashmap1);
    System.out.println(hashmap2);

}

输出将是......

{variable1=Description 1, variable2=Description 2}
{1=Y, 2=Y}

比较并返回给定值的HashMap

1 个答案: