17. public boolean equals(Object obj) { 18. if (this == obj) 19. return true; 20. if (obj == null) 21. return false; 22. if (getClass() != obj.getClass()) 23. return false; 24. VolatileTest other = (VolatileTest) obj; 25. if (url == null) { 26. if (other.url !
public boolean equals(Object anObject) { if (this == anObject) { return true; } if (anObject instanceof String) { String anotherString = (String)anObject; int n = count; if (n == anotherString.count) { char v1[] = value; char v2[] = anotherString.value; int i = offset; in...
The != operator does the exact opposite of the == operator. If the two variables are not equal, the expression is evaluated to true. If the two variables are equal, the expression is evaluated to false. The < operator is evaluated to true, if the variable on the left side of the ...
* @throws UnsupportedOperationException if the specified list or * its list-iterator does not support the {@code set} operation. * @since 1.4 */publicstaticvoidrotate(List<?>list,int distance){if(listinstanceofRandomAccess||list.size()<ROTATE_THRESHOLD)rotate1(list,distance);elserotate2(list,...
13、Java中equal和==的区别是什么? publicclassTest1{publicstaticvoidmain(String args[]){ String a="1234"; String b="1234"; String c= newString("1234"); System.out.println(a==b); System.out.println(a==c); System.out.println(a.equals(c)); ...
It is illegal for a lambda expression to return a value in some branches but not in others. For example,(int x) -> { if (x >= 0) return 1; }is invalid. lambda表达式的方法体中如果有分支语句那么必须要保证有效返回值 The program in Listing 6.6 shows how to use lambda expressions for...
a negative integer, zero, or a positive integer as the first argument is less than, equal to, or greater than the second. Throws: NullPointerException- if an argument is null and this comparator does not permit null arguments ClassCastException- if the arguments' types prevent them from bein...
importjava.math.BigDecimal;publicclassBigDecimalExample{publicstaticvoidmain(String[]args){BigDecimalnum1=newBigDecimal("10");doublenum2=10.0;if(num1.compareTo(BigDecimal.valueOf(num2))==0){System.out.println("num1 equals num2");}else{System.out.println("num1 does not equal num2");}}} ...
Optional<Book>book=...;// this is prone to be empty// Preferif(book.isPresent()){Book theBook=book.get();...// do something with "theBook"}else{...// do something that does not call book.get()} 不过,要记住isPresent()-get()团队信誉不好,所以谨慎使用。考虑检查下一个问题,这些问...
If you test a file you own (the -r -w or -x tests), but the permission tested does not have the owner bit set, a non- zero (false) exit status will be returned even though the file may have the group or other bit set for that permis- ...