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Why isn't try/catch Exceptions working for Gson.fromJson()?

I've been getting com.google.gson.JsonSyntaxException from calling Gson.fromJson(), so added a catch(Exception) logic, but the error is never getting caught and just getting thrown!
Here's what I have:
Request request = new Request.Builder()
.url(getOrderUrlWithId)
.get()
.build();
try {
Response response = this.okHttpClient.newCall(request).execute();
GetOrderResult orderResult = gson.fromJson(gson.toJson(response.body().string()), GetOrderResult.class);
response.close();
} catch (IOException e) {
log.error("Error retrieving order : " + e.getMessage(), e);
throw new RuntimeException(e);
} catch (Exception e) {
log.error("Error happening for client PO: " + clientPO, e);
return null;
}
When I run the test I get "com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was STRING at line 1 column 1 path $
"
Why isn't the error getting caught?
Here's the Stack trace:
com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was STRING at line 1 column 1 path $
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:226)
at com.google.gson.Gson.fromJson(Gson.java:927)
at com.google.gson.Gson.fromJson(Gson.java:892)
at com.google.gson.Gson.fromJson(Gson.java:841)
at com.google.gson.Gson.fromJson(Gson.java:813)
at com.hub.fulfill.circlegraphics.getOrdersByCgOrderId(CircleGraphicsApi.java:164)

You need to catch JsonSyntaxException like this
For Kotlin
catch(e: JsonSyntaxException){
//show toast/snackabar/log here
}
For Java
catch(JsonSyntaxException e){
//show toast/snackabar/log here
}
Earlier I was also catching java.lang.IllegalStateException but it didn't worked.
Seems the root exception here is JsonSyntaxException and thus, we need to catch this one.
It worked for me!

when(...).thenReturn(null) points that you use some mocking library (jMock, Mockery or simular). And you define that if fromJson("test", Fulfillment.class) is called mock should return null. Actual method fromJson is not invoked as you already defined result.
If you want expection to be thrown, then remove line
when(gson.fromJson("test", Fulfillment.class)).thenReturn(null);

Figured it out. So turns out #Slf4j's log.error() call shows the exception as an error in Google StackDriver, hence telling me I've been getting millions of errors.

Java show me long error but missing in my log file

Hi all I know its a stupid question but I'm trying everything.
My game server show me a very long error which is too long for console and can see the top of it, but it is missing from my log and I can't see the details of this error.
Can somebody help me on how can I capture that error:
private void fix(L2PcInstance pl, int playerPoints)
{
try
{
IAchievement arc = Achievements.getInstance().GetAchivment(_id, pl.getAchivmentLevelbyId(_id) + 1);
if ((arc != null) && (playerPoints > arc.getNeedPoints()))
{
Achievements.getInstance().reward(pl, arc);
fix(pl, playerPoints);
}
}
catch (Exception e)
{
_log.error(getClass().getSimpleName() + ": Error in fix: " + e);
}
}
the error
the line 96 is
fix(pl, playerPoints);
but the error is missing from my log im try to capture the console to txt file from command
java myserver.jar > capturemyconsole.txt but again it's showing error in console that the txt is missing. How is this possible ? Thanks for your time and help :)
and sorry for my bad english :(

You method fix calls itself, with the same arguments, causing stack overflow...
Should add some modification to the arguments, or some more condition to the recursion...

You can catch "Error" instead of "Exception" and then log
[...] catch (Error e)
{
_log.error(getClass().getSimpleName() + ": Error in fix: " + e, e);
}
In Your current code StackOverflowException (which is not a child of Exception) is propagated without going into catch block. Remember to put additional "e" parameter to log full stacktrace.
It's not a good practice to catch Error, but it'll answer Your question.
More info: try/catch on stack overflows in java?

log the exception in spring using aspectJ?

Please don't hesitate to edit the question or to ask more details about the questin.
I know I can log the ArithmeticException of the below method using the aspectJ as,
public void afterThrowingAspect(){
System.out.println("This is afterThrowingAspect() !");
int i=2/0;
System.out.println("i value : "+i);
}
The AspectJ class has,
#AfterThrowing(pointcut = "execution(* com.pointel.aop.test1.AopTest.afterThrowingAspect(..))",throwing= "error")
public void logAfterError(JoinPoint joinPoint,Throwable error) {
System.out.println("Hi jacked Method name : " + joinPoint.getSignature().getName());
log.info("Method name : " + joinPoint.getSignature().getName());
log.info("Error report is : " + error);
}
Normally I can handle exception using the TRY and CATCH block and log the errors in the every CATCH block as ,
public void someMehtod(){
try{
int i=2/0;
System.out.println("i value : "+i);
}catch{ArithmeticException err){
log.info("The exception you got is : " + err);
}
}
But I don't like to do the logging like with every single catch block individually in all the java classes of my project like ,
log.info("The exception you got is : " + err);
I would like to do the logging inside CATCH block in my application using the aspectJ class.
Hope you are all understand my question.Thanks.

Its possible to simply remove the try/catch from your code and simply log the exception in your aspect.
public void someMehtod(){
int i=2/0;
System.out.println("i value : "+i);
}
Because you don't re-throw the exception in the aspect then it won't bubble up. Although this is possible I strongly advise you to think more about what you are trying to do here. Why do you need to log the fact that an exception has been thrown? Exceptions aren't necessarily only for errors but can occur in normal code journeys. Simply logging only the exception name is unlikely to help you debug the problem. Therefore, you will probably want a bespoke log message for each catch block. If you do find repetition you could create a method to log out the result.
Hope this helps,
Mark

Print Alfresco exception

I've some problem printing the exception stack trace for Alfresco Exception.
On debug mode, step by step under Eclipse IDE I'm able to see the message when the exception is raised inspecting the Exception object but, when I send the error message to console output it's always null.
The exception is raised by this instruction:
try {
UpdateResult[] results = WebServiceFactory.getRepositoryService().update(cml);
}
catch (Exception ex) {
System.out.println(" " + ex.getStackTrace());
System.out.println("ERROR - createContent : " + ex.getMessage());
}
(in that case I tryed to write on a folder that not exists on repository) and inspecting the ex object on eclipse I can see the message:
java.lang.IllegalStateException: Failed to resolve to a single NodeRef with parameters (store=workspace:SpacesStore uuid=null path=/app:company_home/cm:UploadFromJava), found 0 nodes.
but ex.getMessage() returns null
Anyone could help me?
thanks,
Andrea

Implementing a method in this way:
NamedValue setNameProperty(String name) throws AlfrescoRuntimeException
{
try {
return Utils.createNamedValue(Constants.PROP_NAME, name);
}
catch (Exception ex) {
throw new AlfrescoRuntimeException(ex.getMessage());
}
}
The message is correclty printed with e.printStackTrace();

Try to replace your package in the log4j.properties from debug to error

How to display stack trace on a caught exception?

I have a generic function that prints exceptions (using log4j):
private void _showErrorMessage(Exception e) {
log.error(e.getClass() + ": " + e.getMessage() + ": " + e.getCause() + "\n" + e.getStackTrace().toString());
}
Instead of seeing the stack trace I'm seeing:
[Ljava.lang.StackTraceElement;#49af7e68
How can I view the stack trace of the exception properly?
update
log.error(e) <- shows the error, but doesn't show stack trace

Your logging framework should have the ability to log exceptions, so simply passing the exception to the proper .error(Object, Throwable) call should be enough:
log4j can do it
commons logging can do it
java.util.logging can do it
If your logging framework can't do that, or you need the stack trace in a String for any other reason, then it becomes a bit harder. You'll have to create a PrintWriter wrapping a StringWriter and call .printStackTrace() on the Exception:
StringWriter sw = new StringWriter();
ex.printStackTrace(new PrintWriter(sw));
String stacktrace = sw.toString();

Have you tried?
private void _showErrorMessage(Exception e) {
log.error("Hey! got an exception", e);
}

I use the ExceptionUtils#getFullStackTrace method of Jakarta Commons Lang

Throwable.getStackTrace returns an array of StackTraceElements, hence the toString method is returning a textual representation of the array itself.
In order to actually retrieve the stack trace information, one would have to go through each StackTraceElement to get more information.

You could also look at the Guava libraries from Google.
Throwables.getStackTraceAsString(Throwable throwable)

The exact answer to your question is that you should call Log4J like this:
private void _showErrorMessage(Exception e) {
log.error(e.getClass() + ": " + e.getMessage() + ": " + e.getCause(), e);
}
Although I would dispense with the call to e.getCause() because the stacktrace will give that to you anyway, so:
private void _showErrorMessage(Exception e) {
log.error(e.getClass() + ": " + e.getMessage(), e);
}
ExceptionUtils is fine if you really need a string of the stacktrace, but since you are using Log4J, you lose a lot by not utilizing its built in exception handling.

Exception Stacktrace logging shows two methods for this purpose, one based on Apache Commons and another using the standard JDK method.