ADDITIONAL SYSTEM INFORMATION :
Picked up _JAVA_OPTIONS: -Dawt.useSystemAAFontSettings=gasp
java version "1.8.0_151"
Java(TM) SE Runtime Environment (build 1.8.0_151-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.151-b12, mixed mode)

A DESCRIPTION OF THE PROBLEM :
Javadoc of method ArrayList.ensureCapacity does not restrict the capacity of the ArrayList. Sample program:

public class A {
   public static void main(String args[]) {
      ArrayList al = new ArrayList();
      al.ensureCapacity(Integer.MAX_VALUE);
   }
}

Steps to reproduce:

1. Compile above program
2. Run it using Oracle HotSpot java

Current result:

Exception in thread "main" java.lang.OutOfMemoryError: Requested array size exceeds VM limit
at java.util.Arrays.copyOf(Arrays.java:3210)
at java.util.Arrays.copyOf(Arrays.java:3181)
at java.util.ArrayList.grow(ArrayList.java:265)
at java.util.ArrayList.ensureExplicitCapacity(ArrayList.java:239)
at java.util.ArrayList.ensureCapacity(ArrayList.java:219)
at A.main(A.java:6)

Expected result:

The ArrayList capacity increased by Integer.MAX_VALUE.