Package io.higson.runtime.profiler.jdbc.proxy

Class ProxyExceptionHandler

java.lang.Object

io.higson.runtime.profiler.jdbc.proxy.ProxyExceptionHandler

public abstract class ProxyExceptionHandler
extends Object

This is a helper exception handler to be used by all classes related to DataSourceProxy: - ConnectionProxy - StatementProxy - PreparedStatementProxy

Each of the above classes is defined as a java dynamic proxy (java.lang.reflect.Proxy) and uses its own InvocationHandler to handle proxy logic and then invoke delegate method. However, if delegate method throws an exception, the InvocationHandler receives that exception wrapped in InvocationTargetException which is a checked exception.

Now, the JDK dynamic proxy spec says that: If a checked exception is thrown by this method [...] then an UndeclaredThrowableException [...] will be thrown by the method invocation on the proxy instance. This would not be a correct behaviour of proxy, as proxy needs to be fully transparent. That's why the proxy logic must catch InvoctionTargetException and unwrap it using this helper class.

See Also:

• InvocationHandler
• UndeclaredThrowableException
• ConnectionProxy
• StatementProxy
• PreparedStatementProxy

Constructor Summary

Constructors

Constructor	Description
ProxyExceptionHandler()

Method Summary

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ProxyExceptionHandler

public ProxyExceptionHandler()