Apex Code
The insert DML statement in the example causes a DmlException because we’re inserting a merchandise item without setting any of its required fields. This is the exception error that you see in the debug log.
Account ac = new Account();
insert ac;
Anonymous Error
Line: 2, Column: 1
System.DmlException: Insert failed. First exception on row 0; first error: REQUIRED_FIELD_MISSING, Required fields are missing: [Name]: [Name]
try {
Account ac = new Account();
insert ac;
} catch(DmlException e) {
System.debug('The following exception has occurred: ' + e.getMessage());
}
Notice that the request status in the Developer Console now reports success. This is because the code handles the exception.
try {
Account ac = new Account();
insert ac;
// This doesn't execute since insert causes an exception
System.debug('Statement after insert.');
} catch(DmlException e) {
System.debug('The following exception has occurred: ' + e.getMessage());
}
In the new debug log entry, notice that you don’t see a debug message of Statement after insert. This is because this debug statement occurs after the exception caused by the insertion and never gets executed.
try {
Account ac = new Account();
insert ac;
} catch(DmlException e) {
System.debug('The following exception has occurred: ' + e.getMessage());
}
// This will get executed
System.debug('Statement after insert.');
Alternatively, you can include additional try-catch blocks.
try {
Account ac = new Account();
insert ac;
} catch(DmlException e) {
System.debug('The following exception has occurred: ' + e.getMessage());
}
try {
System.debug('Statement after insert.');
// Insert other records
}
catch (Exception e) {
// Handle this exception here
}
The finally block always executes regardless of what exception is thrown, and even if no exception is thrown. Let’s see it used in action. Execute the following
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