= in Java / Android mean? (bit
Possible Duplicate:
Shortcut “or-assignment” (|=) operator in Java
I found the following example code in the Android SDK docs:
boolean retValue = false;
retValue |= mActionBarHelper.onCreateOptionsMenu(menu);
retValue |= super.onCreateOptionsMenu(menu);
Can anyone show me equivalent code, to demonstrate what this does?
Note: I assume the method calls return a boolean value, so I like to see an example what this looks like as an if-else construct.
Shorthand for or with myself and assign to me, though it is non-short circuit or instead of logical or . As it is available as a short version of assigning and or:ing sometimes used anyway with booleans, as there is no ||=. But important note: in this case it will call both methods even though retValue might already be true
So equivalent (logic wise) statements can be several, but some would be:
boolean a = mActionBarHelper.onCreateOptionsMenu(menu);
boolean b = super.onCreateOptionsMenu(menu);
boolean retValue = a || b;
or
boolean retValue = mActionBarHelper.onCreateOptionsMenu(menu);
retValue = super.onCreateOptionsMenu(menu) || retValue;
| applied to a boolean is just a simple boolean OR.
boolean retValue = false;
retValue = retValue | mActionBarHelper.onCreateOptionsMenu(menu);
retValue = retValue | super.onCreateOptionsMenu(menu);
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