tests: allow to set target java version, use D8 as fallback converter

jadx-plugins/jadx-java-convert/src/main/java/jadx/plugins/input/javaconvert/D8Converter.java

@@ -0,0 +1,53 @@
+package jadx.plugins.input.javaconvert;
+
+import java.nio.file.Path;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.android.tools.r8.CompilationFailedException;
+import com.android.tools.r8.CompilationMode;
+import com.android.tools.r8.D8;
+import com.android.tools.r8.D8Command;
+import com.android.tools.r8.Diagnostic;
+import com.android.tools.r8.DiagnosticsHandler;
+import com.android.tools.r8.OutputMode;
+
+public class D8Converter {
+	private static final Logger LOG = LoggerFactory.getLogger(D8Converter.class);
+
+	public static void run(Path path, Path tempDirectory) throws CompilationFailedException {
+		D8Command d8Command = D8Command.builder(new LogHandler())
+				.addProgramFiles(path)
+				.setOutput(tempDirectory, OutputMode.DexIndexed)
+				.setMode(CompilationMode.DEBUG)
+				.setMinApiLevel(30)
+				.setIntermediate(true)
+				.setDisableDesugaring(true)
+				.build();
+		D8.run(d8Command);
+	}
+
+	private static class LogHandler implements DiagnosticsHandler {
+		@Override
+		public void error(Diagnostic diagnostic) {
+			LOG.error("D8 error: {}", format(diagnostic));
+		}
+
+		@Override
+		public void warning(Diagnostic diagnostic) {
+			LOG.warn("D8 warning: {}", format(diagnostic));
+		}
+
+		@Override
+		public void info(Diagnostic diagnostic) {
+			LOG.info("D8 info: {}", format(diagnostic));
+		}
+
+		public static String format(Diagnostic diagnostic) {
+			return diagnostic.getDiagnosticMessage()
+					+ ", origin: " + diagnostic.getOrigin()
+					+ ", position: " + diagnostic.getPosition();
+		}
+	}
+}

jadx-plugins/jadx-java-convert/src/main/java/jadx/plugins/input/javaconvert/DxConverter.java

@@ -43,7 +43,7 @@ public class DxConverter {
 			throw new RuntimeException("dx exception: " + e.getMessage(), e);
 		}
 		if (result != 0) {
-			throw new RuntimeException("Java to dex conversion error, code: " + result + "\n errors: " + dxErrors);
+			throw new RuntimeException("Java to dex conversion error, code: " + result + ", errors: " + dxErrors);
 		}
 	}
 }

jadx-plugins/jadx-java-convert/src/main/java/jadx/plugins/input/javaconvert/JavaConvertLoader.java

@@ -156,7 +156,12 @@ public class JavaConvertLoader {
 		Path tempDirectory = Files.createTempDirectory("jadx-");
 		result.addTempPath(tempDirectory);
 
-		DxConverter.run(path, tempDirectory);
+		try {
+			DxConverter.run(path, tempDirectory);
+		} catch (Exception e) {
+			LOG.warn("DX convert failed, trying D8");
+			D8Converter.run(path, tempDirectory);
+		}
 
 		LOG.debug("Converted to dex: {}", path.toAbsolutePath());
 		result.addConvertedFiles(collectFilesInDir(tempDirectory));