Replace space indent with tabs

bramble-api/build.gradle

@@ -5,6 +5,7 @@ targetCompatibility = 1.8
 apply plugin: 'ru.vyarus.animalsniffer'
 apply plugin: 'witness'
 apply from: 'witness.gradle'
+apply plugin: 'checkstyle'
 
 dependencies {
 	implementation "com.google.dagger:dagger:$dagger_version"

bramble-core/build.gradle

@@ -7,6 +7,7 @@ apply plugin: 'idea'
 apply plugin: 'witness'
 apply from: 'witness.gradle'
 apply from: '../dagger.gradle'
+apply plugin: 'checkstyle'
 
 dependencies {
 	implementation project(path: ':bramble-api', configuration: 'default')

bramble-core/src/main/java/org/briarproject/bramble/mailbox/UrlConverter.java

@@ -9,9 +9,9 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 @NotNullByDefault
 interface UrlConverter {
 
-   /**
-    * Converts a raw onion address, excluding the .onion suffix, into an
-    * HTTP URL.
-    */
-   String convertOnionToBaseUrl(String onion);
+	/**
+	 * Converts a raw onion address, excluding the .onion suffix, into an
+	 * HTTP URL.
+	 */
+	String convertOnionToBaseUrl(String onion);
 }

bramble-java/build.gradle

@@ -6,6 +6,7 @@ apply plugin: 'idea'
 apply plugin: 'witness'
 apply from: 'witness.gradle'
 apply from: '../dagger.gradle'
+apply plugin: 'checkstyle'
 
 configurations {
 	tor

briar-android/build.gradle

@@ -1,6 +1,10 @@
 apply plugin: 'com.android.application'
 apply plugin: 'witness'
 apply from: 'witness.gradle'
+apply plugin: 'checkstyle'
+// Need to manually apply this as the Java plugin is not applied to this module hence this is not
+// done automatically.
+apply from: "${rootProject.rootDir}/gradle/checkstyle.gradle"
 
 def getStdout = { command, defaultValue ->
 	def stdout = new ByteArrayOutputStream()

briar-android/src/main/java/org/briarproject/briar/android/view/QrCodeView.java

@@ -16,48 +16,48 @@ import androidx.annotation.UiThread;
 
 public class QrCodeView extends FrameLayout {
 
-    private final ImageView qrCodeImageView;
-    private boolean fullscreen = false;
-    private FullscreenListener listener;
+	private final ImageView qrCodeImageView;
+	private boolean fullscreen = false;
+	private FullscreenListener listener;
 
-    public QrCodeView(@NonNull Context context, @Nullable AttributeSet attrs) {
-        super(context, attrs);
-        LayoutInflater inflater = (LayoutInflater) context
-                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
-        inflater.inflate(R.layout.qr_code_view, this, true);
-        qrCodeImageView = findViewById(R.id.qr_code);
-        ImageView fullscreenButton = findViewById(R.id.fullscreen_button);
-        fullscreenButton.setOnClickListener(v -> {
-                    fullscreen = !fullscreen;
-                    if (!fullscreen) {
-                        fullscreenButton.setImageResource(
-                                R.drawable.ic_fullscreen_black_48dp);
-                    } else {
-                        fullscreenButton.setImageResource(
-                                R.drawable.ic_fullscreen_exit_black_48dp);
-                    }
-                    if (listener != null)
-                        listener.setFullscreen(fullscreen);
-                }
-        );
-    }
+	public QrCodeView(@NonNull Context context, @Nullable AttributeSet attrs) {
+		super(context, attrs);
+		LayoutInflater inflater = (LayoutInflater) context
+				.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
+		inflater.inflate(R.layout.qr_code_view, this, true);
+		qrCodeImageView = findViewById(R.id.qr_code);
+		ImageView fullscreenButton = findViewById(R.id.fullscreen_button);
+		fullscreenButton.setOnClickListener(v -> {
+					fullscreen = !fullscreen;
+					if (!fullscreen) {
+						fullscreenButton.setImageResource(
+								R.drawable.ic_fullscreen_black_48dp);
+					} else {
+						fullscreenButton.setImageResource(
+								R.drawable.ic_fullscreen_exit_black_48dp);
+					}
+					if (listener != null)
+						listener.setFullscreen(fullscreen);
+				}
+		);
+	}
 
-    @UiThread
-    public void setQrCode(Bitmap qrCode) {
-        qrCodeImageView.setImageBitmap(qrCode);
-        // Simple fade-in animation
-        AlphaAnimation anim = new AlphaAnimation(0.0f, 1.0f);
-        anim.setDuration(200);
-        qrCodeImageView.startAnimation(anim);
-    }
+	@UiThread
+	public void setQrCode(Bitmap qrCode) {
+		qrCodeImageView.setImageBitmap(qrCode);
+		// Simple fade-in animation
+		AlphaAnimation anim = new AlphaAnimation(0.0f, 1.0f);
+		anim.setDuration(200);
+		qrCodeImageView.startAnimation(anim);
+	}
 
-    @UiThread
-    public void setFullscreenListener(FullscreenListener listener) {
-        this.listener = listener;
-    }
+	@UiThread
+	public void setFullscreenListener(FullscreenListener listener) {
+		this.listener = listener;
+	}
 
-    public interface FullscreenListener {
-        void setFullscreen(boolean fullscreen);
-    }
+	public interface FullscreenListener {
+		void setFullscreen(boolean fullscreen);
+	}
 
 }

briar-api/build.gradle

@@ -5,6 +5,7 @@ targetCompatibility = 1.8
 apply plugin: 'ru.vyarus.animalsniffer'
 apply plugin: 'witness'
 apply from: 'witness.gradle'
+apply plugin: 'checkstyle'
 
 dependencies {
 	implementation project(path: ':bramble-api', configuration: 'default')

briar-core/build.gradle

@@ -7,6 +7,7 @@ apply plugin: 'idea'
 apply plugin: 'witness'
 apply from: 'witness.gradle'
 apply from: '../dagger.gradle'
+apply plugin: 'checkstyle'
 
 dependencies {
 	implementation project(path: ':briar-api', configuration: 'default')

config/checkstyle/checkstyle.xml

@@ -0,0 +1,19 @@
+<!DOCTYPE module PUBLIC
+          "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
+          "https://checkstyle.org/dtds/configuration_1_3.dtd">
+<module name="Checker">
+  <property name="tabWidth" value="4"/>
+  <property name="charset" value="UTF-8"/>
+  <module name="LineLength">
+    <property name="fileExtensions" value="java"/>
+    <property name="max" value="1000"/>
+    <property name="ignorePattern" value="^package.*|^import.*|a href|href|http://|https://|ftp://"/>
+  </module>
+  <module name="TreeWalker">
+    <module name="RegexpSinglelineJava">
+      <property name="format" value="^\t* +\t*\S"/>
+      <property name="message" value="Line has leading space characters; indentation should be performed with tabs only."/>
+      <property name="ignoreComments" value="true"/>
+    </module>
+  </module>
+</module>

gradle/checkstyle.gradle

@@ -0,0 +1,29 @@
+task checkstyleMain(type: Checkstyle) {
+    source 'src/main/java'
+    include '**/*.java'
+    classpath = files()
+    reports {
+        xml {
+            destination file("build/reports/checkstyle/main.xml")
+        }
+        html {
+            destination file("build/reports/checkstyle/main.html")
+        }
+    }
+    check.dependsOn it
+}
+
+task checkstyleTest(type: Checkstyle) {
+    source 'src/test/java'
+    include '**/*.java'
+    classpath = files()
+    reports {
+        xml {
+            destination file("build/reports/checkstyle/test.xml")
+        }
+        html {
+            destination file("build/reports/checkstyle/test.html")
+        }
+    }
+    check.dependsOn it
+}