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Q) Hierarchy of Exception classes




A)
 
->RuntimeException is unchecked exception that’s why their children also coming under unchecked exception.
->super class of all exception classes is “throwable”.
->throwable has 2 sub classes
 1) Error class –very very dangerous ex: static flow
 2) Exception class
->in java applications java.long.Error class and its sub classes representing exceptions can’t be handled.
So, Errors are not handled by JVM. Only some JVM manufacturers handle those errors.
Ex: stack over flow
->Java.long.Exception and its sub classes represent abnormal events. That can be handled in java applications.

Generally
Error- the java compiler rising
Exception- the JVM rising

->java long.Exception class has two kinds of sub classes
1) unchecked exception classes
2) checked exception classes

->java.long.RuntimeException is the only sub class of Exception which is unchecked. All other sub classes of Exception classes are checked.
->All sub classes of java.long.RuntimeException also are unchecked.
->Error can coming under unchecked because can’t be handles are coming under unchecked.
->All abnormal scenarios are pre estimated that classes are developed.

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