자바 집합 프레임 워 크 분석 (3) - List 집합 ArrayList 인 스 턴 스 와 Iterator 교체 기 소스 코드 분석

public class ArrayListDemo2 {

	public static void main(String[] args) {
		ArrayList<Object> al = new ArrayList<Object>();
		al.add(new Person("asdf", 25));
		al.add(new Person("asdf1", 32));
		al.add(new Person("asd2f", 44));
		al.add(new Person("asdf3", 12));
		al.add(new Person("asd4f", 54));
		al.add(new Person("asd4f", 54));

		al = singleElement(al);
		Iterator it = al.iterator();
		while (it.hasNext()) {

			Person p = (Person) it.next();

			sop(p.getname() + "...." + p.getage());

		}
		//   remove         equals  
		sop(al.remove(new Person("asd2f", 44)));

	}

	public static ArrayList singleElement(ArrayList al) {
		ArrayList<Object> newal = new ArrayList();
		ListIterator it = al.listIterator();
		while (it.hasNext()) {
			Object obj = it.next();
			// contains     equals  ，             
			if (!newal.contains(obj))
				newal.add(obj);

		}
		return newal;
	}

	private static void sop(Object o) {

		System.out.println(o);

	}

}

class Person {

	private String name;
	private int age;

	Person(String name, int age) {
		this.name = name;
		this.age = age;

	}

	public String getname() {

		return name;
	}

	public int getage() {

		return age;
	}

	//   equals               
	public boolean equals(Object obj) {
		if (!(obj instanceof Person))
			return false;
		Person p = (Person) obj;
		//       
		System.out.println(this.getname() + "..." + p.name);
		return this.name.equals(p.name) && this.age == p.age;

	}

}

public interface Iterator<E> {
   
    boolean hasNext();

   
    E next();

    void remove();
}

ListIterator it = al.listIterator();

private class Itr implements Iterator<E> {
	
	int cursor = 0;

	int lastRet = -1;

	int expectedModCount = modCount;
}

public boolean hasNext() {
            return cursor != size();
	}

public E next() {
            checkForComodification();
	    try {
		E next = get(cursor);
		lastRet = cursor++;
		return next;
	    } catch (IndexOutOfBoundsException e) {
		checkForComodification();
		throw new NoSuchElementException();
	    }
	}

while (it.hasNext()) {
			Object obj = it.next();
			// contains     equals  ，             
			if (!newal.contains(obj))
				newal.add(obj);

		}