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<title>SWIG:Examples:java:constants</title>
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<body bgcolor="#ffffff">
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<tt>SWIG/Examples/java/constants/</tt>
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<H2>Wrapping C Constants</H2>
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<tt>$Header: /cvs/projects/SWIG/Examples/java/constants/Attic/index.html,v 1.1.2.2 2001/06/08 11:20:50 cheetah Exp $</tt><br>
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When SWIG encounters C preprocessor macros and C declarations that look like constants,
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it creates Java constant with an identical value. Click <a href="example.i">here</a>
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to see a SWIG interface with some constant declarations in it.
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<h2>Accessing Constants from Java</h2>
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Click <a href="main.java">here</a> to see a Java program that prints out the values
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of the constants contained in the above file.
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<li>The values of preprocessor macros are converted into Java constants.
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<li>Types are inferred by syntax (e.g., "3" is an integer and "3.5" is a float).
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<li>Character constants such as 'x' are converted into Java strings.
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<li>C string literals such as "Hello World" are converted into Java strings.
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<li>Macros that are not fully defined are simply ignored. For example:
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is ignored because SWIG has no idea what type of variable this would be.
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<li>Expressions are allowed provided that all of their components are defined. Otherwise, the constant is ignored.
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<li>Certain C declarations involving 'const' are also turned into Java constants.
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<li>The constants that appear in a SWIG interface file do not have to appear in any sort
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of matching C source file since the creation of a constant does not require linkage
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to a stored value (i.e., a value held in a C global variable or memory location).