1 files changed, 117 insertions, 0 deletions
diff --git a/java/org/brotli/wrapper/dec/DecoderJNI.java b/java/org/brotli/wrapper/dec/DecoderJNI.java
new file mode 100755
index 0000000..ffd3ce9
--- /dev/null
+++ b/java/org/brotli/wrapper/dec/DecoderJNI.java
@@ -0,0 +1,117 @@
+/* Copyright 2017 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+package org.brotli.wrapper.dec;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+
+/**
+ * JNI wrapper for brotli decoder.
+ */
+class DecoderJNI {
+  private static native ByteBuffer nativeCreate(long[] context, ByteBuffer customDictionary);
+  private static native void nativePush(long[] context, int length);
+  private static native ByteBuffer nativePull(long[] context);
+  private static native void nativeDestroy(long[] context);
+
+  enum Status {
+    ERROR,
+    DONE,
+    NEEDS_MORE_INPUT,
+    NEEDS_MORE_OUTPUT,
+    OK
+  };
+
+  static class Wrapper {
+    private final long[] context = new long[2];
+    private final ByteBuffer inputBuffer;
+    private Status lastStatus = Status.NEEDS_MORE_INPUT;
+
+    Wrapper(int inputBufferSize, ByteBuffer customDictionary) throws IOException {
+      if (customDictionary != null && !customDictionary.isDirect()) {
+        throw new IllegalArgumentException("LZ77 dictionary must be direct ByteBuffer");
+      }
+      this.context[1] = inputBufferSize;
+      this.inputBuffer = nativeCreate(this.context, customDictionary);
+      if (this.context[0] == 0) {
+        throw new IOException("failed to initialize native brotli decoder");
+      }
+    }
+
+    void push(int length) {
+      if (length < 0) {
+        throw new IllegalArgumentException("negative block length");
+      }
+      if (context[0] == 0) {
+        throw new IllegalStateException("brotli decoder is already destroyed");
+      }
+      if (lastStatus != Status.NEEDS_MORE_INPUT && lastStatus != Status.OK) {
+        throw new IllegalStateException("pushing input to decoder in " + lastStatus + " state");
+      }
+      if (lastStatus == Status.OK && length != 0) {
+        throw new IllegalStateException("pushing input to decoder in OK state");
+      }
+      nativePush(context, length);
+      parseStatus();
+    }
+
+    private void parseStatus() {
+      long status = context[1];
+      if (status == 1) {
+        lastStatus = Status.DONE;
+      } else if (status == 2) {
+        lastStatus = Status.NEEDS_MORE_INPUT;
+      } else if (status == 3) {
+        lastStatus = Status.NEEDS_MORE_OUTPUT;
+      } else if (status == 4) {
+        lastStatus = Status.OK;
+      } else {
+        lastStatus = Status.ERROR;
+      }
+    }
+
+    Status getStatus() {
+      return lastStatus;
+    }
+
+    ByteBuffer getInputBuffer() {
+      return inputBuffer;
+    }
+
+    ByteBuffer pull() {
+      if (context[0] == 0) {
+        throw new IllegalStateException("brotli decoder is already destroyed");
+      }
+      if (lastStatus != Status.NEEDS_MORE_OUTPUT) {
+        throw new IllegalStateException("pulling output from decoder in " + lastStatus + " state");
+      }
+      ByteBuffer result = nativePull(context);
+      parseStatus();
+      return result;
+    }
+
+    /**
+     * Releases native resources.
+     */
+    void destroy() {
+      if (context[0] == 0) {
+        throw new IllegalStateException("brotli decoder is already destroyed");
+      }
+      nativeDestroy(context);
+      context[0] = 0;
+    }
+
+    @Override
+    protected void finalize() throws Throwable {
+      if (context[0] != 0) {
+        /* TODO: log resource leak? */
+        destroy();
+      }
+      super.finalize();
+    }
+  }
+}