Can I find out the return value before returning while debugging in IntelliJ?

Practical stepping stones to the return value

Before we return a value in a method, let's visualize the scene that leads to it using IntelliJ's powerful debugging features.

Expression evaluation during the debug

IntelliJ's Evaluate Expression (Run -> Evaluate Expression) command lets you execute a return statement or any other expression spotlighted by a breakpoint in the current context.

Breakpoints and stepping: your debug compass

Set breakpoints within your method to create checkpoints: you can observe the return values and track changes in local variables. The Step Over (F8) command allows you to examine the return value without entering another method, hence not leaving the current method scope.

Adjust settings for a constant return value display

In the debugger settings, you can enable "Show method return values" for IntelliJ to monitor and display the returns in the debugger panel after each method execution.

Getting a sneak peek at the return queue

Design your breakpoints to provide the most insights before the method completes. A breakpoint on the return line helps you anticipate the return value effectively inside its native context.

public int computeValue() {
    // Some serious business logic here
    int result = heavyLifting();  // result did the heavy lifting, deserves a peek!🙈
    return result;  // Breakpoint here enlightens us with the return value
}
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Successfully dealing with performance challenges

Method breakpoints: a necessary evil?

Method breakpoints might seem helpful until you realize they could affect performance. Instead, consider posturing your breakpoints on the line immediately prior to a method's result becoming apparent.

Post-return breakpoints: the aftermath detectives

Establishing breakpoints on the immediate line after a method call can expose the return value without incurring the performance cost of method breakpoints:

int result = computeValue(); // Breakpoint here uncovers the return alibi
processResult(result); // ... and life continues
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Instant value inspection for the busy developer

IntelliJ's Quick Evaluate Expression feature (CTRL + ALT + F8) is like an espresso—delivers swift results without disturbing your debugging workflow.

Acing advanced visualization techniques

Treat for the method fortune tellers

Just as in real-time stock market updates, you can 'follow the returns' with IntelliJ's watch method return values feature in the debugger panel.

Picture Perfect with IntelliJ

For those who prefer visual learning, IntelliJ provides images and visual aid in the debugger panel—say, a debug "picture tutorial."

Avoid temp variables, keep the neighbourhood clean

You need not litter your code with temporary variables just to preview return values. Utilize the debugger's watch expressions feature to inspect the return statement's evaluation directly.