Java do nothing
Question:
What is the equivalent to Python’s pass in Java? I realize that I could use continue or not complete the body of a statement to achieve that effect, but I like having a pass statement.
Answers:
;
; is the empty statement. Usually, you don’t need it – you can just put nothing in the brackets for an empty loop – but it can be useful.
Just use a semi-colon ;, it has the same effect.
If you want something noticeable, you can use
assert true;
This will allow you to have something that a reader can recognize or that can be searched for.
There is no (strict) equivalent since in java you have to specify the return type for the method in its declaration which is then checked against a computed type of the following the return statement. So for methods that have a return type – neither semicollon nor leaving empty braces will work;
I personally use: throw new java.lang.UnsupportedOperationException("Not supported yet."); – this is searchable, alerts you that the method is not implemented and is compatible with the strict return types.
I feel, there is no construct in Java identical to pass in Python. This is mostly because Java is a statically typed language where as Python is a dynamically typed language. More so when you are defining a method / function. In that context, the provided answers are valid / correct only for a method that returns void.
For example for a Python function
def function_returns_void:
pass
you can have a Java method
public void function_returns_void(){}
or
public void function_returns_void(){;}
but when a method is supposed to return a value, while pass may still work in Python, one will stuck with compilation problem when not returning a value.
I normally use something like:
"".isEmpty(); // do nothing
It’s useful to be able to have a line of code which does nothing when debugging. You can put a breakpoint on that line, which is especially useful if it would usually be an empty block of code (e.g. empty catch block etc), as putting a breakpoint on an empty line can create confusion about where the breakpoint is actually set.
What is the equivalent to Python’s pass in Java? I realize that I could use continue or not complete the body of a statement to achieve that effect, but I like having a pass statement.
;
; is the empty statement. Usually, you don’t need it – you can just put nothing in the brackets for an empty loop – but it can be useful.
Just use a semi-colon ;, it has the same effect.
If you want something noticeable, you can use
assert true;
This will allow you to have something that a reader can recognize or that can be searched for.
There is no (strict) equivalent since in java you have to specify the return type for the method in its declaration which is then checked against a computed type of the following the return statement. So for methods that have a return type – neither semicollon nor leaving empty braces will work;
I personally use: throw new java.lang.UnsupportedOperationException("Not supported yet."); – this is searchable, alerts you that the method is not implemented and is compatible with the strict return types.
I feel, there is no construct in Java identical to pass in Python. This is mostly because Java is a statically typed language where as Python is a dynamically typed language. More so when you are defining a method / function. In that context, the provided answers are valid / correct only for a method that returns void.
For example for a Python function
def function_returns_void:
pass
you can have a Java method
public void function_returns_void(){}
or
public void function_returns_void(){;}
but when a method is supposed to return a value, while pass may still work in Python, one will stuck with compilation problem when not returning a value.
I normally use something like:
"".isEmpty(); // do nothing
It’s useful to be able to have a line of code which does nothing when debugging. You can put a breakpoint on that line, which is especially useful if it would usually be an empty block of code (e.g. empty catch block etc), as putting a breakpoint on an empty line can create confusion about where the breakpoint is actually set.