remove temporary error handling
make attributes iterable
make code parsing of the code attribute lazy

Another huge performance boost. Parsing rt.jar got 3x faster and requires
half the RAM (still half a GB though).
inline readUnsignedShort

Another big performance boost. Unsigned short values are the most common in
class files. Profiling showed that more than ten percent of CPU time was
spent in this method (about 1.1s on my machine for rt.jar). The inlined
version shows almost no time in VisualVM.
get constant pool info types by lookup instead of loop

This only shaves off a tiny amount of time. The new version is not detected
by VisualVM profiling anymore (inlined or compiled to native?). However I
like lookups more than loops anyway if they are possible.
make stack map table lazy; also iterable

Performance improvements are getting smaller.
make exception table iterable