Coding Convention: Difference between revisions
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Simantics coding conventions are gathered in this document. | Simantics coding conventions are gathered in this document. These rules apply to all ''org.simantics'' projects. | ||
==Argument Assumption== | ==Argument Assumption== | ||
Revision as of 10:13, 13 October 2010
Simantics coding conventions are gathered in this document. These rules apply to all org.simantics projects.
Argument Assumption
- All method arguments are non-null unless explicitely stated otherwise in documentation.
<syntaxhighlight lang="java">
/**
* Read the object from a file.
*
* @param file
*/
void read(File file);
/**
* Write or remove existing value.
*
* @param newValue new value or null</t> to remove the existing value
*/
void setValue(Object newValue);
</syntaxhighlight>
Non-null assumption applies in undocumented methods aswell. This method mustn't be called with a null argument.
<syntaxhighlight lang="java">
void read(InputStream is);
</syntaxhighlight>
Return value assumption
- All return values are non-null unless explicitely stated otherwise in documentation.
<syntaxhighlight lang="java">
/**
* Get the value
*
* @return the value
*/
Object get() throws ValueUnavailableException;
/**
* Get possibly existing value
*
* @return the value is exists, otherwise null
*/
Object get();
</syntaxhighlight>
Non-null assumption applies in undocumented methods too. There is always a non-null value returned from this method.
<syntaxhighlight lang="java">
Object get();
</syntaxhighlight>
Trust your assumptions
- You have a code of conduct - give it a chance.
The callee can trust the caller.
<syntaxhighlight lang="java">
Object deserialize(InputStream is) {
int x = is.read();
...
return result;
}
</syntaxhighlight>
And the caller the callee.
<syntaxhighlight lang="java">
System.out.println( serialiser.deserialize( is ) );
</syntaxhighlight>
There is no need to do redundant checking, especially at run-time.
<syntaxhighlight lang="java">
Object deserialize(InputStream is) {
if ( is == null ) throw IllegalArgumentException("Non-null argument");
int x = is.read();
...
return result;
}
</syntaxhighlight>
Nor caller.
<syntaxhighlight lang="java">
Object x = serializer.deserialize( is ); if ( x != null ) System.out.println( x );
</syntaxhighlight>
Use assertions if you must. It sometimes improve quality and debuggability.
<syntaxhighlight lang="java" style="background: #dfd;">
Object deserialize(InputStream is) {
assert( is != null );
...
return result;
}
</syntaxhighlight>