docs: public static JavaMetadata instance( InputStream inputStream,
                                           long length,
                                           String encoding ) throws IOException {
  
          JavaMetadata javaMetadata = new JavaMetadata();
          char[] source = JavaMetadataUtil.getJavaSourceFromTheInputStream(inputStream, length, encoding);
  
          CompilationUnit unit = (CompilationUnit)CompilationUnitParser.runJLS3Conversion(source, true);
          if (unit != null) {
              javaMetadata.packageMetadata = javaMetadata.createPackageMetadata(unit);
              javaMetadata.imports = javaMetadata.createImportMetadata(unit);
              javaMetadata.types = javaMetadata.createTypeMetadata(unit);
  
          }
  
          return javaMetadata;
      }