Difference between revisions of "Coding Convention"
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<syntaxhighlight lang="java"> | <syntaxhighlight lang="java"> | ||
− | + | Object deserialize(InputStream is) { | |
int x = is.read(); | int x = is.read(); | ||
+ | ... | ||
+ | return result; | ||
} | } | ||
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<syntaxhighlight lang="java"> | <syntaxhighlight lang="java"> | ||
− | + | Object deserialize(InputStream is) { | |
if ( is == null ) throw IllegalArgumentException("Non-null argument"); | if ( is == null ) throw IllegalArgumentException("Non-null argument"); | ||
− | + | ... | |
+ | return result; | ||
} | } | ||
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<syntaxhighlight lang="java" style="background: #dfd;"> | <syntaxhighlight lang="java" style="background: #dfd;"> | ||
− | + | Object deserialize(InputStream is) { | |
assert( is != null ); | assert( is != null ); | ||
− | + | ... | |
+ | return result; | ||
} | } | ||
</syntaxhighlight> | </syntaxhighlight> | ||
<br/> | <br/> | ||
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Revision as of 10:09, 13 October 2010
Simantics coding conventions are gathered in this document.
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"); ... 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>