Add already-implemented interfaces Closeable and Flushable to the cache.

okhttp/src/main/java/okhttp3/Cache.java

@@ -16,7 +16,9 @@
 
 package okhttp3;
 
+import java.io.Closeable;
 import java.io.File;
+import java.io.Flushable;
 import java.io.IOException;
 import java.security.cert.Certificate;
 import java.security.cert.CertificateEncodingException;
@@ -131,7 +133,7 @@
  * caching directives. It even offers convenient constants {@link CacheControl#FORCE_NETWORK} and
  * {@link CacheControl#FORCE_CACHE} that address the use cases above.
  */
-public final class Cache {
+public final class Cache implements Closeable, Flushable {
   private static final int VERSION = 201105;
   private static final int ENTRY_METADATA = 0;
   private static final int ENTRY_BODY = 1;
@@ -380,11 +382,11 @@ public long maxSize() {
     return cache.getMaxSize();
   }
 
-  public void flush() throws IOException {
+  @Override public void flush() throws IOException {
     cache.flush();
   }
 
-  public void close() throws IOException {
+  @Override public void close() throws IOException {
     cache.close();
   }
 

okhttp/src/main/java/okhttp3/internal/DiskLruCache.java

@@ -20,6 +20,7 @@
 import java.io.EOFException;
 import java.io.File;
 import java.io.FileNotFoundException;
+import java.io.Flushable;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -81,7 +82,7 @@
  * value, the edit will fail silently. Callers should handle other problems by catching {@code
  * IOException} and responding appropriately.
  */
-public final class DiskLruCache implements Closeable {
+public final class DiskLruCache implements Closeable, Flushable {
   static final String JOURNAL_FILE = "journal";
   static final String JOURNAL_FILE_TEMP = "journal.tmp";
   static final String JOURNAL_FILE_BACKUP = "journal.bkp";
@@ -623,7 +624,7 @@ private synchronized void checkNotClosed() {
   }
 
   /** Force buffered operations to the filesystem. */
-  public synchronized void flush() throws IOException {
+  @Override public synchronized void flush() throws IOException {
     if (!initialized) return;
 
     checkNotClosed();
@@ -632,7 +633,7 @@ public synchronized void flush() throws IOException {
   }
 
   /** Closes this cache. Stored values will remain on the filesystem. */
-  public synchronized void close() throws IOException {
+  @Override public synchronized void close() throws IOException {
     if (!initialized || closed) {
       closed = true;
       return;