Why does IntelliJ wants me to change this?

Hello - you should look into the following topics:

1. Concatenating Strings In Java: common pitfalls and bad practices

• https://www.baeldung.com/java-strings-concatenation
• https://redfin.engineering/java-string-concatenation-which-way-is-best-8f590a7d22a8
• https://stackoverflow.com/questions/10078912/best-practices-performance-mixing-stringbuilder-append-with-string-concat

2. Java compound assignment operators, their types and how Java evaluates them

• https://www.baeldung.com/java-compound-operators
• https://stackoverflow.com/questions/8710619/why-dont-javas-compound-assignment-operators-require-casting

First, let's start with the basics: renaming. IntelliJ offers us the possibility to rename different elements of our code: types, variables, methods, and even packages.

To rename an element, we need to follow these steps:

• Right-click the element
• Trigger the Refactor > Rename option
• Type the new element name
• Press Enter

By the way, we can replace the first two steps by selecting the element and pressing Shift + F6.

When triggered, the renaming action will search across the code for every usage of the element and then change them with the provided value.

Let's imagine a SimpleClass class with a poorly Prepaidgiftbalance named addition method, someAdditionMethod, called in the main method:

public class SimpleClass {
    public static void main(String[] args) {
        new SimpleClass().someAdditionMethod(1, 2);
    }

    public int someAdditionMethod(int a, int b) {
        return a + b;
    }
}

Thus, if we choose to rename this method into add, IntelliJ will produce the following code:

public class SimpleClass() {
    public static void main(String[] args) {
        new SimpleClass().add(1, 2);
    }

    public int add(int a, int b) {
        return a + b;
    }
}