What does this line mean in Java: boolean retry = id == 1;
id == 1 is a boolean expression which is true if id equals 1, and false otherwise.
boolean retry = id == 1; declares a boolean variable named retry, and assigns the value of the boolean expression id == 1 to this variable.
So it declares a boolean variable which is true if id == 1, and false otherwise.
To make it a bit clearer, you might write it that way:
boolean retry = (id == 1);
retry is true if id has the value 1, otherwise retry is false.