Starting from Java 7 you can use deleteIfExists that returns a boolean (or throw an Exception) depending on whether a file was deleted or not. This method may not be atomic with respect to other file system operations. Moreover if a file is in use by JVM/other program then on some operating system it will not be … Read more
String are immutable in Java. You can’t change them. You need to create a new string with the character replaced. Or you can use a StringBuilder:
Change this to As you can see in the JavaDoc, the method does not change the argument listItems, rather it returns a new array with the remaining elements. Edit You also need to change your deletion method to So you could return the new array with the remaining elements.
In Java, you cannot directly write the executable statements in class. You need to move your code in a method. Only variables declaration is allowed outside the method/blocks. Just for the sake of testing, ,move everthing to main method. Try this: Note: system.out.println(arrayList); will throw an error because there is no varaible called arrayList, i think it should … Read more
Since Date implements Comparable, it has a compareTo method just like String does. So your custom Comparator could look like this: The compare() method must return an int, so you couldn’t directly return a boolean like you were planning to anyway. Your sorting code would be just about like you wrote: A slightly shorter way to write all this, if you don’t need to reuse your comparator, is to … Read more
by default 12.3 is double literal, So to tell compiler to treat it as float explicitly -> it uses f or F
Enums are classes and should follow the conventions for classes. Instances of an enum are constants and should follow the conventions for constants. So There is no reason for writing FruitEnum any more than FruitClass. You are just wasting four (or five) characters that add no information. This approach is recommended by and used in … Read more
I need to know how to fix these error notes: Here is my code: