Java Reference
In-Depth Information
inal exception's information and stack trace are
lost
. Earlier Java versions provided no
mechanism to wrap the original exception information with the new exception's informa-
tion to provide a complete stack trace showing where the original problem occurred. This
made debugging such problems particularly difficult.
Chained exceptions
enable an ex-
ception object to maintain the complete stack-trace information from the original excep-
tion. Figure 11.7 demonstrates chained exceptions.
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// Fig. 11.7: UsingChainedExceptions.java
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// Chained exceptions.
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4
public
class
UsingChainedExceptions
5
{
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public
static
void
main(String[] args)
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{
8
try
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{
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method1();
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}
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catch
(Exception exception)
// exceptions thrown from method1
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{
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exception.printStackTrace();
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}
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}
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// call method2; throw exceptions back to main
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public
static
void
method1()
throws
Exception
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{
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try
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{
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method2();
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}
// end try
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catch
(Exception exception)
// exception thrown from method2
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{
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throw
new
Exception(
"Exception thrown in method1"
, exception);
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}
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}
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// call method3; throw exceptions back to method1
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public
static
void
method2()
throws
Exception
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{
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try
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{
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method3();
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}
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catch
(Exception exception)
// exception thrown from method3
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{
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throw
new
Exception(
"Exception thrown in method2"
, exception);
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}
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}
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Fig. 11.7
|
Chained exceptions. (Part 1 of 2.)
