java遍历List中的map的几种方法

java遍历List中的map的几种方法

Student类

public class Student {

    private String name;

    private int age;

    private int taller;

     

    public Student( String name, int age, int taller ) {

        this.name = name;

        this.age = age;

        this.taller = taller;

    }

     

    @Override

    public String toString() {

        StringBuilder builder = new StringBuilder();

        builder.append("Student [name=").append(name).append(", age=").append(age).append(", taller=").append(taller)

                .append("]");

        return builder.toString();

    }

 

    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;

    }

     

    public void setTaller( int taller ) {

        this.taller = taller;

    }

     

    public int getTaller() {

        return taller;

    }

}

测试类

import java.util.ArrayList;

import java.util.HashMap;

import java.util.Iterator;

import java.util.List;

import java.util.Map;

import PubClass.Student;

 

public class ListAddMap {

     

    public static void main( String args[] ) {

         

        List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();

        Map<String, Object> map = new HashMap<String, Object>();

         

        Student stu1 = new Student( "\u5f20\u4e09", 26, 180 );

        Student stu2 = new Student( "\u674e\u56db", 28, 175 );

         

        map.put( "stu1", stu1 );

        map.put( "stu2", stu2 );

        list.add( map );

         

        System.out.println( "方法一 :" );

        for( int i = 0; i < list.size(); i++ ) {

            System.out.println( list.get(i) );

        }

         

        System.out.println( "方法二 :" );

        for( Map<String, Object> mapList : list ) {

            for( String key : mapList.keySet() ) {

                System.out.println( key + "-->" + mapList.get(key) );

            }

        }

         

        System.out.println( "方法三 :" );

        for( int i = 0; i < list.size(); i++ ) {

            Map<String, Object> mapList = list.get(i);

            Iterator<String> it = mapList.keySet().iterator();

            while( it.hasNext() ) {

                String str = (String) it.next();

                System.out.println( "key-->" + str + "\t value-->" + map.get(str) );

            }

        }

    }

     

}

运行结果