pt 1 in reviving the android build (copied from pm 28a1, wish me luck)

mobile/android/thirdparty/com/jakewharton/disklrucache/Util.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2010 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.jakewharton.disklrucache;
+
+import java.io.Closeable;
+import java.io.File;
+import java.io.IOException;
+import java.io.Reader;
+import java.io.StringWriter;
+import java.nio.charset.Charset;
+
+/** Junk drawer of utility methods. */
+final class Util {
+  static final Charset US_ASCII = Charset.forName("US-ASCII");
+  static final Charset UTF_8 = Charset.forName("UTF-8");
+
+  private Util() {
+  }
+
+  static String readFully(Reader reader) throws IOException {
+    try {
+      StringWriter writer = new StringWriter();
+      char[] buffer = new char[1024];
+      int count;
+      while ((count = reader.read(buffer)) != -1) {
+        writer.write(buffer, 0, count);
+      }
+      return writer.toString();
+    } finally {
+      reader.close();
+    }
+  }
+
+  /**
+   * Deletes the contents of {@code dir}. Throws an IOException if any file
+   * could not be deleted, or if {@code dir} is not a readable directory.
+   */
+  static void deleteContents(File dir) throws IOException {
+    File[] files = dir.listFiles();
+    if (files == null) {
+      throw new IOException("not a readable directory: " + dir);
+    }
+    for (File file : files) {
+      if (file.isDirectory()) {
+        deleteContents(file);
+      }
+      if (!file.delete()) {
+        throw new IOException("failed to delete file: " + file);
+      }
+    }
+  }
+
+  static void closeQuietly(/*Auto*/Closeable closeable) {
+    if (closeable != null) {
+      try {
+        closeable.close();
+      } catch (RuntimeException rethrown) {
+        throw rethrown;
+      } catch (Exception ignored) {
+      }
+    }
+  }
+}