refactor: allow to change temp dir using system property JADX_TMP_DIR

jadx-cli/src/main/java/jadx/cli/JadxCLI.java

@@ -7,6 +7,7 @@ import jadx.api.JadxArgs;
 import jadx.api.JadxDecompiler;
 import jadx.api.impl.NoOpCodeCache;
 import jadx.core.utils.exceptions.JadxArgsValidateException;
+import jadx.core.utils.files.FileUtils;
 
 public class JadxCLI {
 	private static final Logger LOG = LoggerFactory.getLogger(JadxCLI.class);
@@ -22,6 +23,7 @@ public class JadxCLI {
 			LOG.error("jadx error: {}", e.getMessage(), e);
 			result = 1;
 		} finally {
+			FileUtils.deleteTempRootDir();
 			System.exit(result);
 		}
 	}

jadx-core/src/main/java/jadx/core/utils/files/FileUtils.java

@@ -10,7 +10,9 @@ import java.io.InputStream;
 import java.io.OutputStream;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.util.ArrayList;
+import java.util.Comparator;
 import java.util.Enumeration;
 import java.util.List;
 import java.util.Objects;
@@ -32,6 +34,9 @@ public class FileUtils {
 	public static final int READ_BUFFER_SIZE = 8 * 1024;
 	private static final int MAX_FILENAME_LENGTH = 128;
 
+	public static final String JADX_TMP_INSTANCE_PREFIX = "jadx-instance-";
+	public static final String JADX_TMP_PREFIX = "jadx-tmp-";
+
 	private FileUtils() {
 	}
 
@@ -70,6 +75,12 @@ public class FileUtils {
 		}
 	}
 
+	public static void makeDirs(@Nullable Path dir) {
+		if (dir != null) {
+			makeDirs(dir.toFile());
+		}
+	}
+
 	public static boolean deleteDir(File dir) {
 		File[] content = dir.listFiles();
 		if (content != null) {
@@ -80,11 +91,28 @@ public class FileUtils {
 		return dir.delete();
 	}
 
+	public static void deleteDir(Path dir) {
+		try {
+			Files.walk(dir)
+					.sorted(Comparator.reverseOrder())
+					.map(Path::toFile)
+					.forEach(File::delete);
+		} catch (Exception e) {
+			throw new JadxRuntimeException("Failed to delete directory " + dir, e);
+		}
+	}
+
 	private static final Path TEMP_ROOT_DIR = createTempRootDir();
 
 	private static Path createTempRootDir() {
 		try {
-			Path dir = Files.createTempDirectory("jadx-instance-");
+			String jadxTmpDir = System.getenv("JADX_TMP_DIR");
+			Path dir;
+			if (jadxTmpDir != null) {
+				dir = Files.createTempDirectory(Paths.get(jadxTmpDir), "jadx-instance-");
+			} else {
+				dir = Files.createTempDirectory(JADX_TMP_INSTANCE_PREFIX);
+			}
 			dir.toFile().deleteOnExit();
 			return dir;
 		} catch (Exception e) {
@@ -92,6 +120,15 @@ public class FileUtils {
 		}
 	}
 
+	public static void deleteTempRootDir() {
+		deleteDir(TEMP_ROOT_DIR);
+	}
+
+	public static void clearTempRootDir() {
+		deleteDir(TEMP_ROOT_DIR);
+		makeDirs(TEMP_ROOT_DIR);
+	}
+
 	public static Path createTempDir(String prefix) {
 		try {
 			Path dir = Files.createTempDirectory(TEMP_ROOT_DIR, prefix);
@@ -104,7 +141,7 @@ public class FileUtils {
 
 	public static Path createTempFile(String suffix) {
 		try {
-			Path path = Files.createTempFile(TEMP_ROOT_DIR, "jadx-tmp-", suffix);
+			Path path = Files.createTempFile(TEMP_ROOT_DIR, JADX_TMP_PREFIX, suffix);
 			path.toFile().deleteOnExit();
 			return path;
 		} catch (Exception e) {
@@ -112,6 +149,14 @@ public class FileUtils {
 		}
 	}
 
+	public static Path createTempFileNoDelete(String suffix) {
+		try {
+			return Files.createTempFile(TEMP_ROOT_DIR, JADX_TMP_PREFIX, suffix);
+		} catch (Exception e) {
+			throw new JadxRuntimeException("Failed to create temp file with suffix: " + suffix, e);
+		}
+	}
+
 	public static void copyStream(InputStream input, OutputStream output) throws IOException {
 		byte[] buffer = new byte[READ_BUFFER_SIZE];
 		while (true) {

jadx-core/src/test/java/jadx/tests/api/IntegrationTest.java

@@ -6,7 +6,6 @@ import java.io.IOException;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
-import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.Arrays;
 import java.util.Collections;
@@ -21,6 +20,7 @@ import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
 import java.util.jar.JarOutputStream;
 
+import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 
 import jadx.api.ICodeInfo;
@@ -119,6 +119,11 @@ public abstract class IntegrationTest extends TestUtils {
 		args.setFsCaseSensitive(false); // use same value on all systems
 	}
 
+	@AfterEach
+	public void after() {
+		FileUtils.clearTempRootDir();
+	}
+
 	public String getTestName() {
 		return this.getClass().getSimpleName();
 	}
@@ -414,7 +419,7 @@ public abstract class IntegrationTest extends TestUtils {
 				temp = FileUtils.createTempFile(suffix);
 			} else {
 				// don't delete on exit
-				temp = Files.createTempFile("jadx", suffix);
+				temp = FileUtils.createTempFileNoDelete(suffix);
 				System.out.println("Temporary file saved: " + temp.toAbsolutePath());
 			}
 			return temp.toFile();

jadx-gui/src/main/java/jadx/gui/ui/MainWindow.java

@@ -77,6 +77,7 @@ import jadx.api.JadxArgs;
 import jadx.api.JavaClass;
 import jadx.api.JavaNode;
 import jadx.api.ResourceFile;
+import jadx.core.utils.files.FileUtils;
 import jadx.gui.JadxWrapper;
 import jadx.gui.jobs.BackgroundExecutor;
 import jadx.gui.jobs.BackgroundWorker;
@@ -1098,6 +1099,8 @@ public class MainWindow extends JFrame {
 		settings.setMainWindowExtendedState(getExtendedState());
 		cancelBackgroundJobs();
 		dispose();
+
+		FileUtils.deleteTempRootDir();
 		System.exit(0);
 	}