List、String的 equals方法

 List 的 equals():

  public boolean equals(Object o) {if (o == this)return true;if (!(o instanceof List))return false;ListIterator<E> e1 = listIterator();ListIterator<?> e2 = ((List<?>) o).listIterator();while (e1.hasNext() && e2.hasNext()) {E o1 = e1.next();Object o2 = e2.next();if (!(o1==null ? o2==null : o1.equals(o2)))return false;}return !(e1.hasNext() || e2.hasNext());}

String的equals()

   public boolean equals(Object anObject) {if (this == anObject) {return true;}if (anObject instanceof String) {String anotherString = (String)anObject;int n = value.length;if (n == anotherString.value.length) {char v1[] = value;char v2[] = anotherString.value;int i = 0;while (n-- != 0) {if (v1[i] != v2[i])return false;i++;}return true;}}return false;}

 Objects.equals(Object a, Object b)

  public static boolean equals(Object a, Object b) {return (a == b) || (a != null && a.equals(b));}