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POwrapping byte array data with SWIG array_class
 

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    <p>I have a C function that returns an unsigned char * that can either be a pointer to a byte array (binary data representing a File..etc) or a pointer to an array of characters. I'm currently using the SWIG <code>%array_class</code> that wraps all C functions that return an unsigned char pointer and creates a Java array utility (SampleArrayUtil.java) to handle the population and retrieval on the Java side. </p> <p>My problem is that I also use wrap the <code>unsigned char *</code> using: <code>%apply char * { unsigned char * };</code> so that I get an array of Strings on the Java side. I don't want to wrap the <code>unsigned char *</code> return value (using <code>%apply char * { unsigned char * };</code>) when I get binary data back, I want to just have the byte array on the Java side. I was thinking of creating another C function to handle the binary data, but I'm unsure how to wrap this new function as it will also return an <code>unsigned char *</code> (see <code>getValueFromRowAsByteArray</code>)</p> <p><strong>C Functions:</strong></p> <pre><code>unsigned char * getValueFromRowAsStringArray(struct result_row *row, attribute_type type, int32_t *len) unsigned char * getValueFromRowAsByteArray(struct result_row *row, attribute_type type, int32_t *len) //*row* input param with data results, *type* input enum type for the data type being requested and *len* is an output param that contains the length of the data being returned. </code></pre> <p><strong>SWIG Interface File for Wrapping C Function Returning unsigned char * (array of char):</strong></p> <pre><code>%module Sample %include "typemaps.i" %include "stdint.i" %include "arrays_java.i" %include "carrays.i" %array_class(unsigned char, SampleArrayUtil); %{ #include "C_API.h" %} %apply char * { unsigned char * }; %include "C_API.h" </code></pre>
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    1. COSo you're looking to have different types returned on the Java interface from the same types on the C side - you want to selectively apply the typemaps? (Just checking we're on the same page before I write an answer)
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    2. CO@awoodland - yes that's correct.
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