Java Core Classes and Threads

This method is used to pre-allocate a space for a certain number of characters, after a StringBuffer has been constructed.

This method is used to extract a single character from a string.

This method returns the number of threads in the group, along with a group, for which this thread is a parent.

This method returns the name of the invoking package.

This method determines whether the string in the question ends with a specified string or not.

This method searches for the first occurrence of a character or substring.

This method displays the call stack for the thread.

If we want to convert all the characters in a string object into a character array, we use the method toCharArray().

getItemSelectable() method can be used to obtain a reference to the Item Selectable object that generate an event.

NullPointer exception is thrown when an application attempts to use null where an object is required.

ArrayIndexOutOfBounds exception is thrown when an attempt is made to access element beyond the index of the array.

Event source is an object that generates an event.

Object of the Scanner class are useful in breaking down the inputs from the user into tokens, and these tokens can be converted into individual basic data types.

The nextToken() is the method of a StringTokenizer() class, and ttype is the filed name.

The PushBackReader class is not directly derived from the Reader class.