Okay, I'm looking at people's answers and wondering how everyone knows...?

Question

In many of the examples I see something like this in the Main.java:

Prompter prompter = new Prompter();
        String story = null;

//This is the block where I'm confused:
 try {
            story = prompter.promptForStory();
        } catch (IOException ioe) {
            ioe.printStackTrace();
        }

//code continues
Template tmpl = new Template(story);
        prompter.run(tmpl);
    }

I understand the big picture concept of trying and catching, but what is the clue that we need one here?

Answer 1 · 2016-07-04T13:34:19Z

July 4, 2016 1:34pm

I'm not familiar with the specific java code you're asking about but there are two categories of exception (checked and unchecked). One group means you messed up ("Unchecked runtime exceptions represent conditions that, generally speaking, reflect errors in your program's logic and cannot be reasonably recovered from at run time."), while others are a result of your code needing to deal with things that have an innate danger of crashing (for example running out of disk space). If you look through the java documentation, a lot of the methods list the potential exceptions they can cause. A good programmer avoid avoidable exceptions (should avoid a try catch to deal with unchecked exceptions) and uses try and catch when exposing themselves to something where crashing may be unavoidable. So you should deal with any potential for checked exceptions, or mark your code with a throws statement (forces the calling code to deal with the potential exception in order to compile). (i hope i got that right - it's been 7 years since i did java 101)

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Aaron Coursolle

Aaron Coursolle

Okay, I'm looking at people's answers and wondering how everyone knows...?

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Simon Coates

Simon Coates