Menu
everyone. I have a rookie question about the returning value in java. Here's my code.
@Override
public long addDrugTreatment(long id, String diagnosis, String drug,
float dosage) throws PatientNotFoundExn {
try {
Patient patient = patientDAO.getPatientByDbId(id);
long tid = patient.addDrugTreatment(diagnosis, drug, dosage);
Connection treatmentConn = treatmentConnFactory.createConnection();
Session session = treatmentConn.createSession(true, Session.AUTO_ACKNOWLEDGE);
MessageProducer producer = session.createProducer(treatmentTopic);
TreatmentDto treatment = null;
ObjectMessage message = session.createObjectMessage();
message.setObject(treatment);
producer.send(message);
return tid;
} catch (PatientExn e) {
throw new PatientNotFoundExn(e.toString());
} catch (JMSException e) {
logger.severe("JMS Error: " + e);
}
}
Eclipse reports a "This method must return a result of type long" error. Yet I did return the tid in the try block; eclipse suggests to add a return value after the try/catch block, which would break the logic. Could you please tell me what wrong here? Thanks.
401
In a try-catch-finally block that has return statements, only the value from the finally block will be returned. When returning reference types, be aware of any updates being done on them in the finally block that could end up in unwanted results.
Yes, we can write a return statement of the method in catch and finally block. There is a situation where a method will have a return type and we can return some value at any part of the method based on the conditions.
In the preceding code, finally block overrides the value returned by try block. Therefore, this would return value 50 because the value returned by try has been overridden by finally block. In the above example program, finally block overrides the value returned by catch block. Therefore, the returned value is 50.
All code after it will be perfectly reachable. And finally returns nothing at all. It is just a block of code that is executed unaware of if there was an exception or not.
Return statement in try catch block java. If we are keeping return statement in try block only there may be a situation of chance of raising exception and try will not execute completely and it goes to catch block that is the reason it expecting a return at catch or end of the method.
Java try and catch. The try statement allows you to define a block of code to be tested for errors while it is being executed. The catch statement allows you to define a block of code to be executed, if an error occurs in the try block. The try and catch keywords come in pairs: try {.
If we return a value in the catch block and we can write a statement at the end of the method after return a value, the code will not execute so it became unreachable code as we know Java does not support unreachable codes. If we return a value in the final block and no need of keeping a return value at the end of the method. Example 1
Whenever try-block executes successfully, then it can always return value for this method; But if any exception is raised & it is handled in the corresponding catch-block –> return statement inside finally-block will return value for this method (after executing any statement inside finally-block before encountering return statement)
When a JMSException is thrown the return value is undefined. When an exception is thrown, control passes immediately to the exception handler. In this case, you log the error. Then control continues from that point which goes to the end of the function without returning a value. You either need to return a value or throw an exception.
191
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
