public static void main(String[] args) {// ArrayList类实现一个可增长的动态数组List<String> list = new ArrayList<String>();// 插入元素list.add("list1");list.add("list2");// 打印list的大小
    System.out.println(list.size());// 按索引移除元素list.remove(0);// 按对象移除元素list.remove("list2");// 打印list的大小
    System.out.println(list.size());// 清空list
    list.clear();
}

public static void main(String[] args) {// LinkedList类实现了链表，可初始化化为空或者已存在的集合LinkedList<String> list = new LinkedList<String>();// 插入元素list.add("list2");list.add("list3");// 向链表头插入数据list.addFirst("list1");// 向链表尾插入数据list.addLast("list4");for (String str : list) {System.out.println(str);}// 获取链表头数据System.out.println("链表头数据:" + list.getFirst());// 获取链表尾数据System.out.println("链表尾数据:" + list.getLast());
}

public static void main(String[] args) {// 创建listList<Integer> list = new ArrayList<Integer>();// 插入元素list.add(2);list.add(0);list.add(3);list.add(4);list.add(1);Collections.sort(list);for (int i : list) {System.out.println(i);}
}

public static void main(String[] args) {ArrayList<String> list = new ArrayList<String>();list.add("一鸣惊人-Y");list.add("人山人海-R");list.add("海阔天空-H");list.add("空前绝后-K");list.add("后来居上-H");Comparator<Object> cmp = Collator.getInstance(java.util.Locale.CHINA);Collections.sort(list, cmp);for (String str : list) {System.out.println(str);}
}

package net.xsoftlab.baike;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
public class TextList {public static void main(String[] args) {List<User> userlist = new ArrayList<User>();userlist.add(new User("Y - 易小星 ", 33));userlist.add(new User("W - 王大锤", 33));Comparator<User> cmp = new ComparatorUser();Collections.sort(userlist, cmp);for (User user : userlist) {System.out.println(user.getName());}}
}
class ComparatorUser implements Comparator<User> {@Overridepublic int compare(User u1, User u2) {// 先按年龄排序int flag = u1.getAge().compareTo(u2.getAge());// 年龄相等比较姓名if (flag == 0) {return u1.getName().compareTo(u2.getName());} else {return flag;}}
}
class User {private String name;private Integer age;public User() {super();}public User(String name, Integer age) {super();this.name = name;this.age = age;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getAge() {return age;}public void setAge(Integer age) {this.age = age;}
}

public static void main(String[] args) {List<String> list = new ArrayList<String>();// 插入元素list.add("list1");list.add("list2");list.add("list3");System.out.println("第一种遍历方法 - >");for (String str : list) {System.out.println(str);}System.out.println("第二种遍历方法 - >");for (int i = 0; i < list.size(); i++) {System.out.println(list.get(i));}System.out.println("第三种遍历方法 - >");Iterator<String> iter = list.iterator();while (iter.hasNext()) {System.out.println(iter.next());}
}

package net.xsoftlab.baike;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
public class RemoveItemFromList {public static void main(String[] args) {List<String> list = new ArrayList<String>();// 插入元素list.add("list1");list.add("list2");list.add("list2");list.add("list3");// 实例化新的list防止因传递地址而达不到测试效果。remove1(new ArrayList<String>(list));remove2(new ArrayList<String>(list));remove2_1(new ArrayList<String>(list));remove3(new ArrayList<String>(list));}public static void remove1(List<String> list) {System.out.print("第一种方法 - > ");try {for (String str : list) {if (str.equals("list2"))list.remove(str);}} catch (Exception e) {System.out.println("移除失败!");}}public static void remove2(List<String> list) {System.out.print("第二种方法 - > ");for (int i = 0; i < list.size(); i++) {String str = list.get(i);if (str.equals("list2"))list.remove(str);}System.out.println(list);System.out.println("也有异常，可以用下面的方法避免。");}public static void remove2_1(List<String> list) {System.out.print("第二种方法修正 - > ");for (int i = 0; i < list.size(); i++) {String str = list.get(i);if (str.equals("list2")) {list.remove(str);// 因移除了元素,位置发生偏移,需要重新对当前位置的元素进行判断。i--;}}System.out.println(list);}public static void remove3(List<String> list) {System.out.print("第三种方法 - > ");Iterator<String> iter = list.iterator();while (iter.hasNext()) {String str = iter.next();if (str.equals("list2"))iter.remove();}System.out.println(list);}
}

public static void main(String[] args) {Map<String, String> map = new HashMap<String, String>();map.put("1", "value1");map.put("2", "value2");map.put("3", "value3");//第一种：普遍使用，二次取值System.out.println("通过Map.keySet遍历key和value：");for (String key : map.keySet()) {System.out.println("key= "+ key + " and value= " + map.get(key));}//第二种System.out.println("通过Map.entrySet使用iterator遍历key和value：");Iterator<Map.Entry<String, String>> it = map.entrySet().iterator();while (it.hasNext()) {Map.Entry<String, String> entry = it.next();System.out.println("key= " + entry.getKey() + " and value= " + entry.getValue());}//第三种：推荐，尤其是容量大时System.out.println("通过Map.entrySet遍历key和value");for (Map.Entry<String, String> entry : map.entrySet()) {System.out.println("key= " + entry.getKey() + " and value= " + entry.getValue());}//第四种System.out.println("通过Map.values()遍历所有的value，但不能遍历key");for (String v : map.values()) {System.out.println("value= " + v);}}