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§1.40 Class NullPointerException

public  class  java.lang.NullPointerException
    extends  java.lang.RuntimeException  (I-§1.42)
{
        // Constructors
    public NullPointerException();	§1.40.1
    public NullPointerException(String  s);	§1.40.2
}

Thrown when an application attempts to use null in a case where an object is required. These include:

Call the instance method of a null object.
Accessing or modifying the field of the null object.
Taking the length of null as if it were an array.
Accessing or modifying the slots of null as if it were an array.
Throwing null as if it were a Throwable value.

Applications should throw instances of this class to indicate other illegal uses of the null object.

NullPointerException

public NullPointerException()

Constructs a NullPointerException with no detail message.

NullPointerException

public NullPointerException(String  s)

Constructs a NullPointerException with the specified detail message.

Parameters:: s -the detail message

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