How to Set a Value in a Map While Debugging in IntelliJ IDEA

How can I set a value in a Map while debugging in IntelliJ IDEA?

// Example of setting a value in a Map during debugging
Map<String, String> myMap = new HashMap<>();
myMap.put("Key1", "Value1");
// In the debugger, set the value like this:
myMap.put("Key2", "NewValue");

Debugging effectively can significantly enhance your development process. IntelliJ IDEA offers powerful debugging capabilities, including the ability to manipulate objects, such as Map entries, during runtime.

// Use Evaluate Expression to set value in Map

// In the debugger, go to Evaluate Expression:
// myMap.put("Key2", "NewValue");

Causes

• You may be trying to analyze or modify data structures while stepping through code.
• You want to test specific scenarios without altering the source code.

Solutions

• Utilize the Evaluate Expression feature in IntelliJ IDEA to interactively change Map values during a debugging session.
• Use watches to monitor Map values and modify them as needed.

Mistake: Attempting to change values in a Map without pausing the debugger.

Solution: Ensure your application is paused at a breakpoint before attempting to modify the Map.

Mistake: Forgetting to check if the key already exists before inserting a new value.

Solution: Use code like myMap.putIfAbsent("Key", "Value") to avoid overwriting existing entries.