kotlin和java和hashmap轉換

碰到一個需求，掃描wifi，然後把掃到的wifi顯示在list中，但是掃出來的wifi總是重複，為了實作去重效果，把list周遊，存儲成map，然後利用map自身的特性，達到去重的目的，然後拿到不重複的map wifi清單，然後再次周遊map，把符合條件的wifi資訊，存儲到新的list中，然後展示這個list，可以實作wifi清單實時掃描顯示

step1:

package com.example.demoanalytic

import android.os.Bundle
import android.support.v7.app.AppCompatActivity
import android.text.TextUtils
import android.util.Log

class MapTestActivity : AppCompatActivity() {
    //     private HashMap<String, StudentBean> map2 = new HashMap<>();
    private var map2: HashMap<String, StudentBean> = HashMap<String, StudentBean>()

    private var wifiList = mutableListOf<StudentBean>()

    private val wifi = "mindor-"

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        /*
                map2.put("1", mStudentBean);
        map2.put("2", mStudentBean2);
        * */

        val mStudentBean = StudentBean()
        val mStudentBean2 = StudentBean()
        val mStudentBean3 = StudentBean()


        mStudentBean.age = 18
        mStudentBean.name = "郭靖"

        mStudentBean2.age = 22
        mStudentBean2.name = "楊過"

        mStudentBean3.age = 32
        mStudentBean3.name = "黃蓉"

        map2["mindor-001"] = mStudentBean
        map2["mindor-002"] =mStudentBean2
        map2["608"] =mStudentBean3


        Log.e("TAG", "$map2")

        /*
          if (!list.isEmpty()) {
            list.clear();
        }
        * */

        if (wifiList.isNotEmpty()){
            wifiList.clear()
        }

        val iter: Iterator<String> = map2.keys.iterator()
        while (iter.hasNext()) {
            val key = iter.next()
            Log.e("TAG", "key:$key")
        /*    if (TextUtils.equals(key, "1")) {
                map2?.let {
                    it[key]?.let { it1 -> wifiList.add(it1) }
                }
            }
                    boolean isData = connectedWifiInfo.getSSID().contains(WIFI_NAME);

            */

            if (key.contains(wifi)){
                map2?.let {
                    it[key]?.let { it1 -> wifiList.add(it1) }
                }
            }

        }

        Log.e("TAG", "key:$wifiList")



    }

}      

package com.example.demoanalytic;

public class StudentBean {

    private String name;

    private int age;



    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
}      

package com.example.demoanalytic;

import android.net.wifi.ScanResult;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.text.TextUtils;
import android.util.Log;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;

public class MapThreeActivity extends AppCompatActivity {
    private CacheMap<String, StudentBean> cacheMap = new CacheMap<>();
    private CacheMap<String, String> map = new CacheMap<>();
    private HashMap<String, StudentBean> map2 = new HashMap<>();
    private List<StudentBean> list;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        list = new ArrayList<>();
        StudentBean mStudentBean = new StudentBean();
        mStudentBean.setName("張飛");
        mStudentBean.setAge(18);
        StudentBean mStudentBean2 = new StudentBean();
        mStudentBean2.setName("關羽");
        mStudentBean2.setAge(21);
        map2.put("1", mStudentBean);
        map2.put("2", mStudentBean2);
        if (!list.isEmpty()) {
            list.clear();
        }
        Iterator<String> iter = map2.keySet().iterator();
        while (iter.hasNext()) {
            String key = iter.next();
            Log.e("TAG", "key:" + key);
            if (TextUtils.equals(key, "1")) {
                list.add(map2.get(key));
            }
        }
        Log.e("TAG", "list:" + list);


    }
}