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- Question: What is the index of
Brightonin the following array?Answer: 2.String[] skiResorts = { "Whistler Blackcomb", "Squaw Valley", "Brighton", "Snowmass", "Sun Valley", "Taos" };
- Question: Write an expression that refers to the string
Brightonwithin the array.
Answer:skiResorts[2].
- Question: What is the value of the expression
skiResorts.length?
Answer: 6.
- Question: What is the index of the last item in the array?
Answer: 5.
- Question: What is the value of the expression
skiResorts[4]?
Answer:Sun Valley
- Exercise: The following program,
WhatHappens, contains a bug. Find it and fix it.
Answer: The program generates a// // This program compiles but won't run successfully. // public class WhatHappens { public static void main(String[] args) { StringBuffer[] stringBuffers = new StringBuffer[10]; for (int i = 0; i < stringBuffers.length; i ++) { stringBuffers[i].append("StringBuffer at index " + i); } } }NullPointerExceptionon line 6. The program creates the array, but does not create the string buffers, so it cannot append any text to them. The solution is to create the 10 string buffers in the loop withnew StringBuffer()as follows:ThisHappenspublic class ThisHappens { public static void main(String[] args) { StringBuffer[] stringBuffers = new StringBuffer[10]; for (int i = 0; i < stringBuffers.length; i ++) { stringBuffers[i] = new StringBuffer(); stringBuffers[i].append("StringBuffer at index " + i); } } }
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