9. The indexOf() Methods



Answer:
erc
The second statement works like this: 
buttercup
The final string could just as easily have been created with a single call: 
    str = str.substring(4,7);


The indexOf() Methods





    

    

    

        

            

                

            

        

    

















    

    





    

        
There are four varieties of indexOf() in the Java library. Only the following may be included on the AP examination:

        

            
                

                    
                        
indexOf( String str )

                    		
                    
                        
Returns the index of the first occurrence of str or -1 if str is not found.

                    		
                

            
        

        


        
For example, the following puts the value 4 into location.

    





    

        

            
String example = "The sea is calm to-night." ;
int location = example.indexOf( "sea" );

        

    





    

        
The following puts the value -1 into location.

    





    

        

            
String example = "The sea is calm to-night." ;
int location = example.indexOf( "rats" );

        

    














    

        

    





    















Question 9:
What does the following put into location?
    String example = "The sea is calm to-night." ;
int location = example.indexOf( "a" );