ADDITIONAL SYSTEM INFORMATION :
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 :
Accordingly to Javadoc (https://docs.oracle.com/javase/8/docs/api/java/lang/Class.html#forName-java.lang.String-) Class.forName method "Returns the Class object associated with the class or interface with the given string name". However, an exception is thrown when executing the following program:

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. Compile above program
2. Run it using Oracle HotSpot java

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
class [[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[Ljava.lang.String;
ACTUAL -
java.lang.ClassNotFoundException: [[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[Ljava/lang/String;
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:264)
at A.main(A.java:11)

---------- BEGIN SOURCE ----------
public class A {
    public static void main(String[] args) {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < 256; i++) {
            sb.append('[');
        }
        sb.append("Ljava.lang.String;");
        String name = sb.toString();
        Class<?> c;
        try {
            c = Class.forName(name);
            System.err.println(c);
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
    }
}
---------- END SOURCE ----------

FREQUENCY : always