Java增强for循环的增删操作代码

for( 元素类型T 元素变量t : 遍历对象obj){
	引用了t 的java 语句;
}

    private static void test() {
        List<String> names = new ArrayList<String>() {{
            add("Hello");
            add("World");
            add("Good");
        }};
        System.out.println("foreach循环");
        for (String name : names) {
            System.out.println(name);
        }
        System.out.println("普通for循环");
        for (int i = 0; i < names.size(); i++) {
            System.out.println(names.get(i));
        }
    }

    private static void test() {
        List<String> names = new ArrayList<String>() {
            {
                this.add("Hello");
                this.add("World");
                this.add("Good");
            }
        };
        System.out.println("foreach循环");
        Iterator var1 = names.iterator();

        while(var1.hasNext()) {
            String name = (String)var1.next();
            System.out.println(name);
        }

        System.out.println("普通for循环");

        for(int i = 0; i < names.size(); ++i) {
            System.out.println((String)names.get(i));
        }

    }

    private static void test() {
        List<String> names = new ArrayList<String>() {{
            add("Hello");
            add("World");
            add("Good");
        }};
        System.out.println("增强for循环");
        for (String name : names) {
            System.out.println(name);
            if ("Hello".equals(name)) {
                names.remove(name);
            }
        }
    }

增强for循环
Hello
Exception in thread "main" java.util.ConcurrentModificationException
	at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:911)
	at java.util.ArrayList$Itr.next(ArrayList.java:861)

        final void checkForComodification() {
            if (modCount != expectedModCount)
                throw new ConcurrentModificationException();
        }

class ArrayList{
	private int modCount;
	public void add();
	public void remove();
	private class Itr implements Iterator<E> {
		int expectedModCount = modCount;
	}
	public Iterator<E> iterator() {
		return new Itr();
	}
}

    /*
     * Private remove method that skips bounds checking and does not
     * return the value removed.
     */
    private void fastRemove(int index) {
        modCount++;
        int numMoved = size - index - 1;
        if (numMoved > 0)
            System.arraycopy(elementData, index+1, elementData, index,
                             numMoved);
        elementData[--size] = null; // clear to let GC do its work
    }

    private static void test() {
        List<String> names = new ArrayList<String>() {{
            add("Hello");
            add("World");
            add("Good");
        }};
        Iterator iterator = names.iterator();
        while (iterator.hasNext()) {
            if (iterator.next().equals("Hello")) {
                iterator.remove();
            }
        }
    }