WifiDiagnostics: migrate to chained logging API

Migrate parameterized log messages in WifiDiagnostics
to the new chained logging API.

Along the way: add DummyLogMessage and FakeLog, to
facilitate testing. (Alternatively, we could bake their
behavior into WifiDiagnosticsTest. But it seems likely
that other tests will want the same behavior.)

While there:
- fix ordering of imports (WifiDiagnostics, WifiDiagnosticsTest)
- remove unused imports (WifiDiagnostics)
- change the level of some WifiDiagnostics log message, to
  fit our new guidelines

BUG=30736898
TEST=wifitests/runtests.sh

Change-Id: If60282adf40d58e80cdaa0d7e1e7008c490d545b
diff --git a/service/java/com/android/server/wifi/DummyLogMessage.java b/service/java/com/android/server/wifi/DummyLogMessage.java
new file mode 100644
index 0000000..726e445
--- /dev/null
+++ b/service/java/com/android/server/wifi/DummyLogMessage.java
@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.wifi;
+
+/** LogMessage implementation that does nothing. */
+public class DummyLogMessage implements WifiLog.LogMessage {
+    @Override
+    public WifiLog.LogMessage r(String value) {
+        return this;
+    }
+
+    @Override
+    public WifiLog.LogMessage c(String value) {
+        return this;
+    }
+
+    @Override
+    public WifiLog.LogMessage c(long value) {
+        return this;
+    }
+
+    @Override
+    public WifiLog.LogMessage c(char value) {
+        return this;
+    }
+
+    @Override
+    public void flush() {
+        // Nothing to do.
+    }
+}
diff --git a/service/java/com/android/server/wifi/FakeWifiLog.java b/service/java/com/android/server/wifi/FakeWifiLog.java
new file mode 100644
index 0000000..69cd725
--- /dev/null
+++ b/service/java/com/android/server/wifi/FakeWifiLog.java
@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.wifi;
+
+/** WifiLog implementation that does nothing. */
+public class FakeWifiLog implements WifiLog {
+    private static final DummyLogMessage sDummyLogMessage = new DummyLogMessage();
+
+    // New-style methods.
+    @Override
+    public LogMessage err(String format) {
+        return sDummyLogMessage;
+    }
+
+    @Override
+    public LogMessage warn(String format) {
+        return sDummyLogMessage;
+    }
+
+    @Override
+    public LogMessage info(String format) {
+        return sDummyLogMessage;
+    }
+
+    @Override
+    public LogMessage trace(String format) {
+        return sDummyLogMessage;
+    }
+
+    @Override
+    public LogMessage dump(String format) {
+        return sDummyLogMessage;
+    }
+
+    // Legacy methods.
+    @Override
+    public void e(String msg) {
+        // Do nothing.
+    }
+
+    @Override
+    public void w(String msg) {
+        // Do nothing.
+    }
+
+    @Override
+    public void i(String msg) {
+        // Do nothing.
+    }
+
+    @Override
+    public void d(String msg) {
+        // Do nothing.
+    }
+
+    @Override
+    public void v(String msg) {
+        // Do nothing.
+    }
+}
diff --git a/service/java/com/android/server/wifi/WifiDiagnostics.java b/service/java/com/android/server/wifi/WifiDiagnostics.java
index 8c0ac14..160cf6b 100644
--- a/service/java/com/android/server/wifi/WifiDiagnostics.java
+++ b/service/java/com/android/server/wifi/WifiDiagnostics.java
@@ -18,10 +18,9 @@
 
 import android.content.Context;
 import android.util.Base64;
-import android.util.Log;
 
-import com.android.internal.annotations.VisibleForTesting;
 import com.android.internal.R;
+import com.android.internal.annotations.VisibleForTesting;
 import com.android.server.wifi.util.ByteArrayRingBuffer;
 import com.android.server.wifi.util.StringUtil;
 
@@ -31,7 +30,6 @@
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.io.PrintWriter;
-import java.lang.StringBuilder;
 import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.Calendar;
@@ -416,7 +414,7 @@
         mRingBuffers = mWifiNative.getRingBufferStatus();
         if (mRingBuffers != null) {
             for (WifiNative.RingBufferStatus buffer : mRingBuffers) {
-                if (DBG) mLog.d("RingBufferStatus is: \n" + buffer.name);
+                if (DBG) mLog.trace("RingBufferStatus is: %").c(buffer.name).flush();
                 if (mRingBufferData.containsKey(buffer.name) == false) {
                     mRingBufferData.put(buffer.name,
                             new ByteArrayRingBuffer(mMaxRingBufferSizeBytes));
@@ -449,7 +447,7 @@
 
             if ((buffer.flag & RING_BUFFER_FLAG_HAS_PER_PACKET_ENTRIES) != 0) {
                 /* skip per-packet-buffer */
-                if (DBG) mLog.d("skipped per packet logging ring " + buffer.name);
+                if (DBG) mLog.trace("skipped per packet logging ring %").c(buffer.name).flush();
                 continue;
             }
 
@@ -466,7 +464,7 @@
 
         if (mWifiNative.startLoggingRingBuffer(
                 mLogLevel, 0, minInterval, minDataSize, buffer.name) == false) {
-            if (DBG) mLog.e("Could not start logging ring " + buffer.name);
+            if (DBG) mLog.warn("Could not start logging ring %").c(buffer.name).flush();
             return false;
         }
 
@@ -475,7 +473,7 @@
 
     private boolean stopLoggingRingBuffer(WifiNative.RingBufferStatus buffer) {
         if (mWifiNative.startLoggingRingBuffer(0, 0, 0, 0, buffer.name) == false) {
-            if (DBG) mLog.e("Could not stop logging ring " + buffer.name);
+            if (DBG) mLog.warn("Could not stop logging ring %").c(buffer.name).flush();
         }
         return true;
     }
@@ -553,7 +551,7 @@
 
         byte[] compressed = bos.toByteArray();
         if (DBG) {
-            mLog.d(" length is:" + (compressed == null? "0" : compressed.length));
+            mLog.dump("length is: %").c(compressed == null ? 0 : compressed.length).flush();
         }
 
         //encode
@@ -561,7 +559,7 @@
                 compressed.length < input.length ? compressed : input , Base64.DEFAULT);
 
         if (DBG) {
-            mLog.d("FwMemoryDump length is :" + result.length());
+            mLog.dump("FwMemoryDump length is: %").c(result.length()).flush();
         }
 
         return result;
@@ -584,7 +582,7 @@
             }
             process.waitFor();
         } catch (InterruptedException|IOException e) {
-            mLog.e("Exception while capturing logcat" + e);
+            mLog.dump("Exception while capturing logcat: %").c(e.toString()).flush();
         }
         return lines;
     }
@@ -597,7 +595,7 @@
         for (int i = 0; i < logLines.length; i++) {
             lines.addLast(logLines[i]);
         }
-        if (DBG) mLog.d("Added " + logLines.length + " lines");
+        if (DBG) mLog.dump("Added % lines").c(logLines.length).flush();
         return lines;
     }
 
diff --git a/tests/wifitests/src/com/android/server/wifi/WifiDiagnosticsTest.java b/tests/wifitests/src/com/android/server/wifi/WifiDiagnosticsTest.java
index ce5ba7b..a2b8203 100644
--- a/tests/wifitests/src/com/android/server/wifi/WifiDiagnosticsTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/WifiDiagnosticsTest.java
@@ -16,12 +16,6 @@
 
 package com.android.server.wifi;
 
-import android.app.test.MockAnswerUtil.AnswerWithArguments;
-import android.content.Context;
-import android.test.suitebuilder.annotation.SmallTest;
-import com.android.internal.R;
-import android.util.LocalLog;
-
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -36,10 +30,18 @@
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
+import android.app.test.MockAnswerUtil.AnswerWithArguments;
+import android.content.Context;
+import android.test.suitebuilder.annotation.SmallTest;
+import android.util.LocalLog;
+
+import com.android.internal.R;
+
 import org.junit.Before;
 import org.junit.Test;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
+import org.mockito.Spy;
 
 import java.io.FileDescriptor;
 import java.io.PrintWriter;
@@ -51,14 +53,12 @@
  */
 @SmallTest
 public class WifiDiagnosticsTest {
-    public static final String TAG = "WifiDiagsTest";
-
     @Mock WifiStateMachine mWsm;
     @Mock WifiNative mWifiNative;
     @Mock BuildProperties mBuildProperties;
     @Mock Context mContext;
     @Mock WifiInjector mWifiInjector;
-    @Mock WifiLog mLog;
+    @Spy FakeWifiLog mLog;
     WifiDiagnostics mWifiDiagnostics;
 
     private static final String FAKE_RING_BUFFER_NAME = "fake-ring-buffer";