Question

When i run the below program i got the exception when for loop begins its execution at i=1031521. How to over come memory usage of this type?

class wwww
    {
        public static void main(String args[])
        {
            String abc[]=new String[4194304];
            String wwf="";
            int s_count=524286;
            for(int i=0;i<4194304;i++)
            {
                System.out.println("----------enter--------"+i);
                abc[i]=""+i;
                System.out.println("----------exit--------"+i);
            }
        }
    }

The exception is:

Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
    at java.util.Arrays.copyOf(Arrays.java:2882)
    at java.lang.AbstractStringBuilder.expandCapacity(AbstractStringBuilder.
java:100)
    at java.lang.AbstractStringBuilder.append(AbstractStringBuilder.java:390
)
    at java.lang.StringBuilder.append(StringBuilder.java:119)
    at wwww.main(wwww.java:12)

Answer 1

This is because your your uses up all the heap space allocated to your jvm.

You can use argument while running the program to specify the heap size that you would like to allocate.

This is an example:

java -Xmx256m MyClass

Here a maximum of 256 MB of heap space will be allocated