Java other special Operators

The dot (.) operator is used to select members of a class or object instance:
int i = myObject.length;  //Retrieve the value of an instance variable
                         //(of an object) or a static variable (of a class).
myObject.someMethod( );   //A method to be invoked on an object or class
  • The new operator is used to create objects out of a class:
    Object o = new Object( );          // o has reference to new object 
                                       // of Object type (class)
    int hours = new Date().getHours(); // create a new object and invoke a 
                                       // method in it without assigning the object 
    The instanceof operator is used to test whether an object is an instance of a class:
    Boolean b;
    String str = "foo";
    b = ( str instanceof String ); // true, str is a String
    b = ( str instanceof Object ); // also true, as String is an Object
    b = ( str instanceof Date );   // false, str is not a Date or subclass
                                   // of Date
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