Convert server to an Android project

To simplify the device server-side build, use gradle to create an APK,
even if we use it as a simple jar, by running its main() method.

server/.gitignore

@@ -1,4 +1,8 @@
-*.class
-*.jar
-*.dex
-/gen
+*.iml
+.gradle
+/local.properties
+/.idea/
+.DS_Store
+/build
+/captures
+.externalNativeBuild

server/Makefile

@@ -1,92 +0,0 @@
-.PHONY: jar push run clean compile compiletests test
-
-SRC_DIR := src
-GEN_DIR := gen
-CLS_DIR := classes
-CLS_DEX := classes.dex
-TEST_SRC_DIR := tests
-TEST_CLS_DIR := test_classes
-TEST_LIBS := /usr/share/java/junit4.jar:/usr/share/java/hamcrest-core.jar
-
-BUILD_TOOLS := $(ANDROID_HOME)/build-tools/26.0.2
-AIDL := $(BUILD_TOOLS)/aidl
-ifeq ($(OS),Windows_NT)
-	DX := $(BUILD_TOOLS)/dx.bat
-else
-	DX := $(BUILD_TOOLS)/dx
-endif
-
-ANDROID_JAR := $(ANDROID_HOME)/platforms/android-26/android.jar
-
-AIDL_SRC := android/view/IRotationWatcher.aidl
-SRC := com/genymobile/scrcpy/ScrCpyServer.java \
-	com/genymobile/scrcpy/ControlEvent.java \
-	com/genymobile/scrcpy/ControlEventReader.java \
-	com/genymobile/scrcpy/DesktopConnection.java \
-	com/genymobile/scrcpy/Device.java \
-	com/genymobile/scrcpy/DisplayInfo.java \
-	com/genymobile/scrcpy/EventController.java \
-	com/genymobile/scrcpy/Ln.java \
-	com/genymobile/scrcpy/Options.java \
-	com/genymobile/scrcpy/Point.java \
-	com/genymobile/scrcpy/Position.java \
-	com/genymobile/scrcpy/ScreenInfo.java \
-	com/genymobile/scrcpy/ScreenStreamer.java \
-	com/genymobile/scrcpy/ScreenStreamerSession.java \
-	com/genymobile/scrcpy/Size.java \
-	com/genymobile/scrcpy/wrappers/DisplayManager.java \
-	com/genymobile/scrcpy/wrappers/InputManager.java \
-	com/genymobile/scrcpy/wrappers/ServiceManager.java \
-	com/genymobile/scrcpy/wrappers/WindowManager.java \
-
-TEST_SRC := com/genymobile/scrcpy/ControlEventReaderTest.java \
-
-# generate classnames from filepath
-TEST_CLS := $(subst /,.,$(basename $(TEST_SRC)))
-
-JAR := scrcpy-server.jar
-MAIN := com.genymobile.scrcpy.ScrCpyServer
-
-AIDL_GEN := $(AIDL_SRC:%.aidl=$(GEN_DIR)/%.java)
-AIDL_CLS := $(AIDL_SRC:%.aidl=$(CLS_DIR)/%.class)
-SRC_CLS := $(SRC:%.java=$(CLS_DIR)/%.class)
-CLS := $(AIDL_CLS) $(SRC_CLS)
-
-ALL_JAVA := $(AIDL_GEN) $(addprefix $(SRC_DIR)/,$(SRC))
-ALL_TESTS := $(addprefix $(TEST_SRC_DIR)/,$(TEST_SRC))
-
-jar: $(JAR)
-
-$(AIDL_GEN): $(GEN_DIR)/%.java : $(SRC_DIR)/%.aidl
-	mkdir -p $(GEN_DIR)
-	"$(AIDL)" -o$(GEN_DIR) $(SRC_DIR)/$(AIDL_SRC)
-
-compile: $(ALL_JAVA)
-	@mkdir -p "$(CLS_DIR)"
-	javac -source 1.7 -target 1.7 \
-		-cp "$(ANDROID_JAR)" \
-		-d "$(CLS_DIR)" -sourcepath $(SRC_DIR):$(GEN_DIR) \
-		$(ALL_JAVA)
-
-$(JAR): $(ALL_JAVA)
-	# we cannot track easily class dependencies, so execute compile only when jar is outdated
-	+$(MAKE) compile
-	"$(DX)" --dex --output=$(CLS_DEX) $(CLS_DIR)
-	jar cvf $(JAR) classes.dex
-
-push: jar
-	adb push $(JAR) /data/local/tmp/
-
-run: push
-	adb shell "CLASSPATH=/data/local/tmp/$(JAR) app_process /system/bin $(MAIN)"
-
-clean:
-	rm -rf $(CLS_DEX) $(CLS_DIR) $(GEN_DIR) $(JAR) $(TEST_CLS_DIR)
-
-compiletests: compile $(ALL_TESTS)
-	@mkdir -p "$(TEST_CLS_DIR)"
-	javac -cp "$(TEST_LIBS):$(ANDROID_JAR):$(CLS_DIR)" -d "$(TEST_CLS_DIR)" -sourcepath "$(TEST_SRC_DIR)" $(ALL_TESTS)
-
-test:
-	+$(MAKE) compiletests
-	java -cp "$(TEST_LIBS):$(ANDROID_JAR):$(CLS_DIR):$(TEST_CLS_DIR)" org.junit.runner.JUnitCore $(TEST_CLS)

server/build.gradle

@@ -0,0 +1,26 @@
+apply plugin: 'com.android.application'
+
+android {
+    compileSdkVersion 26
+    defaultConfig {
+        applicationId "com.genymobile.scrcpy"
+        minSdkVersion 21
+        targetSdkVersion 26
+        versionCode 1
+        versionName "1.0"
+        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+    }
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+        }
+    }
+}
+
+dependencies {
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    testImplementation 'junit:junit:4.12'
+    androidTestImplementation 'com.android.support.test:runner:1.0.1'
+    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.1'
+}

server/proguard-rules.pro

@@ -0,0 +1,21 @@
+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile

server/src/main/AndroidManifest.xml

@@ -0,0 +1,2 @@
+<!-- not a real Android application, it is run by app_process manually -->
+<manifest package="com.genymobile.scrcpy"/>

server/src/main/aidl/android/view/IRotationWatcher.aidl

@@ -20,6 +20,6 @@ package android.view;
 /**
  * {@hide}
  */
-oneway interface IRotationWatcher {
-    void onRotationChanged(int rotation);
+interface IRotationWatcher {
+    oneway void onRotationChanged(int rotation);
 }

server/src/main/java/com/genymobile/scrcpy/Device.java

@@ -40,6 +40,12 @@ public final class Device {
     }
 
     private ScreenInfo computeScreenInfo(int maximumSize) {
+        // Compute the video size and the padding of the content inside this video.
+        // Principle:
+        // - scale down the great side of the screen to maximumSize (if necessary);
+        // - scale down the other side so that the aspect ratio is preserved;
+        // - ceil this value to the next multiple of 8 (H.264 only accepts multiples of 8)
+        // - this may introduce black bands, so store the padding (typically a few pixels)
         DisplayInfo displayInfo = serviceManager.getDisplayManager().getDisplayInfo();
         boolean rotated = (displayInfo.getRotation() & 1) != 0;
         Size deviceSize = displayInfo.getSize();

server/src/main/java/com/genymobile/scrcpy/ScreenStreamerSession.java

@@ -53,9 +53,7 @@ public class ScreenStreamerSession {
         List<String> command = new ArrayList<>();
         command.add("screenrecord");
         command.add("--output-format=h264");
-        if (videoSize != null) {
-            command.add("--size=" + videoSize.getWidth() + "x" + videoSize.getHeight());
-        }
+        command.add("--size=" + videoSize.getWidth() + "x" + videoSize.getHeight());
         command.add("-");
         Process process = new ProcessBuilder(command).start();
         process.getOutputStream().close();