Parse method of BasicDexFileReader - arrays

Question

I would like to know if I can use the parse method of BasicDexFileReader to load a dexfile which is decrypted into a byte array?
public void parse(byte[] dexBytes) throws IllegalArgumentException, IOException/*,
RefNotFoundException */ {
// Get a DalvikValueReader on the input stream.
reader = new DalvikValueReader(dexBytes, FILE_SIZE_OFFSET);
readHeader();
readStrings();
readTypes();
}
I would be glad if someone can explain what exactly is the purpose of parse method and can it be used in a way i have asked.
Thanks

Answer 1

Take a look at DexMaker.java, which needs to solve this problem for generating code rather than decrypting it.
Here's the relevant sample:
byte[] dex = ...;
/*
* This implementation currently dumps the dex to the filesystem. It
* jars the emitted .dex for the benefit of Gingerbread and earlier
* devices, which can't load .dex files directly.
*
* TODO: load the dex from memory where supported.
*/
File result = File.createTempFile("Generated", ".jar", dexCache);
result.deleteOnExit();
JarOutputStream jarOut = new JarOutputStream(new FileOutputStream(result));
jarOut.putNextEntry(new JarEntry(DexFormat.DEX_IN_JAR_NAME));
jarOut.write(dex);
jarOut.closeEntry();
jarOut.close();
try {
return (ClassLoader) Class.forName("dalvik.system.DexClassLoader")
.getConstructor(String.class, String.class, String.class, ClassLoader.class)
.newInstance(result.getPath(), dexCache.getAbsolutePath(), null, parent);
} catch (ClassNotFoundException e) {
throw new UnsupportedOperationException("load() requires a Dalvik VM", e);
} catch (InvocationTargetException e) {
throw new RuntimeException(e.getCause());
} catch (InstantiationException e) {
throw new AssertionError();
} catch (NoSuchMethodException e) {
throw new AssertionError();
} catch (IllegalAccessException e) {
throw new AssertionError();
}