Creating an Array of Objects in Java
When creating an array of objects in Java, the syntax can be misleading for beginners. Unlike C , where new A[4] initializes an array of four objects, Java's A[] arr = new A[4]; only creates references (pointers) to objects.
To instantiate the actual objects, you must manually allocate each reference:
<code class="java">A[] arr = new A[4]; for (int i = 0; i < 4; i++) { arr[i] = new A(); }</code>
This is necessary because Java does not allocate memory for the objects automatically. Only the references to the objects are initialized. This two-step process may seem cumbersome, but it provides greater flexibility and control over object creation.
In the given example, each element of the arr array represents a distinct object, and you can access its functions and variables without encountering null pointer exceptions. This is unlike the case where you only create references, which would result in null pointer exceptions.
The Java approach differs from C 's dynamic memory allocation, which simplifies object creation by handling allocation and initialization in a single step. However, Java's two-step process allows for more fine-tuned control over object lifecycle management.
The above is the detailed content of How Does Java\'s Array of Objects Initialization Differ from C ?. For more information, please follow other related articles on the PHP Chinese website!