content: // Protocol Buffers - Google's data interchange format
  // Copyright 2008 Google Inc.  All rights reserved.
  // https://developers.google.com/protocol-buffers/
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  package com.google.protobuf;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertFalse;
  import static org.junit.Assert.assertNotEquals;
  import static org.junit.Assert.fail;
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  import org.junit.Before;
  import org.junit.Test;
  
  public abstract class AbstractSchemaTest<T extends MessageLite> {
    private Schema<T> schema;
  
    @Before
    public void setup() {
      schema = schema();
      registerSchemas();
    }
  
    // Subclass should override this method if it needs to register more than one schemas.
    protected void registerSchemas() {
      // Register this schema with the runtime to support processing of nested messages.
      Protobuf.getInstance().registerSchemaOverride(schema.newInstance().getClass(), schema);
    }
  
    protected abstract Schema<T> schema();
  
    protected abstract ExperimentalMessageFactory<? extends T> messageFactory();
  
    @SuppressWarnings("unused")
    protected List<ByteBuffer> serializedBytesWithInvalidUtf8() throws IOException {
      return Collections.emptyList();
    }
  
    @Test
    public void randomMessageShouldRoundtrip() throws IOException {
      roundtrip("", messageFactory().newMessage());
    }
  
    @Test
    public void invalidUtf8StringParsing() throws IOException {
      for (ByteBuffer invalidUtf8Bytes : serializedBytesWithInvalidUtf8()) {
        Reader reader = BinaryReader.newInstance(invalidUtf8Bytes, /* bufferIsImmutable= */ true);
  
        T newMsg = schema.newInstance();
        try {
          schema.mergeFrom(newMsg, reader, ExtensionRegistryLite.getEmptyRegistry());
          fail("should throw invalid ");
        } catch (InvalidProtocolBufferException expected) {
        }
      }
    }
  
    @Test
    public void mergeFromByteArrayFastPathMayThrowIndexOutOfBoundsException() throws IOException {
      if (!Android.isOnAndroidDevice()) {
        // Skip this test if not on Android.
        return;
      }
      byte[] data = messageFactory().newMessage().toByteArray();
      int exceptionCount = 0;
      for (int i = 0; i <= data.length; i++) {
        byte[] truncatedData = Arrays.copyOf(data, i);
        try {
          T message = schema.newInstance();
          // Test that this method throws the expected exceptions.
          schema.mergeFrom(message, truncatedData, 0, i, new ArrayDecoders.Registers());
        } catch (InvalidProtocolBufferException e) {
          // Ignore expected exceptions.
        } catch (IndexOutOfBoundsException e) {
          exceptionCount += 1;
        }
      }
      assertNotEquals(0, exceptionCount);
    }
  
    protected static final <M extends MessageLite> void roundtrip(
        String failureMessage, M msg, Schema<M> schema) throws IOException {
      byte[] serializedBytes = ExperimentalSerializationUtil.toByteArray(msg, schema);
      assertEquals(failureMessage, msg.getSerializedSize(), serializedBytes.length);
  
      // Now read it back in and verify it matches the original.
      if (Android.isOnAndroidDevice()) {
        // Test the fast path on Android.
        M newMsg = schema.newInstance();
        schema.mergeFrom(
            newMsg, serializedBytes, 0, serializedBytes.length, new ArrayDecoders.Registers());
        schema.makeImmutable(newMsg);
        assertEquals(failureMessage, msg, newMsg);
      }
      M newMsg = schema.newInstance();
      Reader reader = BinaryReader.newInstance(ByteBuffer.wrap(serializedBytes), true);
      schema.mergeFrom(newMsg, reader, ExtensionRegistryLite.getEmptyRegistry());
      schema.makeImmutable(newMsg);
  
      assertEquals(failureMessage, msg, newMsg);
    }
  
    protected final void roundtrip(String failureMessage, T msg) throws IOException {
      roundtrip(failureMessage, msg, schema);
    }
  
    protected final ExperimentalTestDataProvider data() {
      return messageFactory().dataProvider();
    }
  
    protected List<T> newMessagesMissingRequiredFields() {
      return Collections.emptyList();
    }
  
    @SuppressWarnings("unchecked")
    @Test
    public void testRequiredFields() throws Exception {
      for (T msg : newMessagesMissingRequiredFields()) {
        if (schema.isInitialized(msg)) {
          assertEquals("", msg.toString());
          msg = (T) msg.toBuilder().build();
        }
        assertFalse(schema.isInitialized(msg));
      }
    }
  }
  