Exceptions in java are any abnormal, unexpected events or extraordinary conditions that may occur at runtime. They could be file not found exception, unable to get connection exception and so on. On such conditions java throws an exception object. 

When a program violates the semantic constraints of the Java programming
 language, the Java virtual machine signals this error to the program as
 an exception.

Java Exceptions are basically Java objects. No Project can never escape a java error exception.