How to Avoid NullPointerExceptions When Initializing Arrays of Objects?

How to Resolve NullPointerException for Arrays of Objects

When initializing an array of objects, it's crucial to avoid encountering the infamous NullPointerException. This exception occurs when you attempt to perform operations on an object that lacks an initialized state.

In the provided example, a class named ResultList is defined, containing two fields (name and value). An array boll is declared to hold five instances of this class. However, the code fails with a NullPointerException when assigning a value to the first element's name field:

ResultList[] boll = new ResultList[5];
boll[0].name = "iiii";

To resolve this exception, the issue lies in failing to initialize each element of the array. When creating the array, it's essentially a set of empty spaces reserved for ResultList objects. To prevent the NullPointerException, explicitly initialize each element with the new keyword:

boll[0] = new ResultList();

This line creates a new object in the first element of boll, effectively ensuring that it's a valid object with accessible fields. Subsequent interactions with boll[0] (such as setting the name property) will no longer result in the NullPointerException.

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