Question:
How do I convert a String object to a StringBuffer object? I tried to put a String object into a stringBuffer using a cast, but I got an invalidcast error message.

Answer:
String is an immutable class derived only from Object. Thereforeyou cannot cast it to another type. In C++ a copy constructor will be invoked, if available, when performing an assignment, but thereis no equivalent behavior in Java.

To convert a String toa StringBuffer you must create a new StringBuffer instance with theString as an argument to the constructor. For example:

String str = "a string";StringBuffer strbuf;strbuf = new StringBuffer(str);