The mystery of instanceof and type conversion

public class Colorpoint{public static void Main (string[] args) {String s = null; System.out.println (S instanceof String); ColorPoint CP = (colorpoint) new Object ();}}

Output what? To compile and pass?

Debugging found that you can javac the past, but Java will output false, and then throw an exception.

public class Colorpoint{public static void Main (string[] args) {System.out.println (New ColorPoint () instanceof String);}}

Output what? Can I compile the past?

Try to find that the compilation is not over.

Import java.util.*;p ublic class Colorpoint{<span style= "White-space:pre" ></span>public static void Main ( String[] args) {<span style= "white-space:pre" ></span>colorpoint cp = (colorpoint) new Point (); <span Style= "White-space:pre" ></span>}}class point{}

Can you compile the past? compilation does not pass.

A few requirements for instanceof

1, when the instanceof do the operand is null, the return value is false,

2. If two operands are classes, one of them must be a subtype of the other

Questions about type conversions

Like Instanceof, when two is a class then one must be another subclass, or it will not compile, and as for conversion, it is the run-time thing.

The mystery of instanceof and type conversion