The Extract Field refactoring lets you declare a new field and initialize it with the selected expression. The original expression is replaced with the usage of the field.
Extract a field in place
Position the caret within a piece of code you want to extract into a field.
Press Ctrl+Alt+F or from the main menu, select Refactor | Extract Field.
Select an expression you want introduce as a field. If IntelliJ IDEA detects more than one occurrence in your code, it lets you specify which occurrences to replace. You can press Ctrl+Alt+F twice to open the Extract Field dialog where you can specify additional details, such as visibility options, or options for initializing your variable.
Example
Let's extract the anotherClass.intValue(); variable into a field. As a result, IntelliJ IDEA changes the selected variable name to number and declares it as the private int number field.
Before
After
public class Class {
AnotherClass anotherClass;
public void method() {
int a = 1;
int b = a + anotherClass.intValue();
int c = b + anotherClass.intValue();
}
}
public class Class {
public AnotherClass anotherClass;
private int number;
public void method() {
int a = 1;
number = anotherClass.intValue();
int b = a + number;
int c = b + number;
}
}
