* See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.graph;

import static com.google.common.graph.GraphConstants.ENDPOINTS_MISMATCH;
import static com.google.common.truth.Truth.assertThat;
import static com.google.common.truth.TruthJUnit.assume;
import static org.junit.Assert.assertThrows;
import static org.junit.Assert.assertTrue;

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.graph;

import static com.google.common.graph.GraphConstants.ENDPOINTS_MISMATCH;
import static com.google.common.graph.TestUtil.assertEdgeNotInGraphErrorMessage;
import static com.google.common.truth.Truth.assertThat;
import static com.google.common.truth.TruthJUnit.assume;

          + "adjacentNode(node) if you already have a node, or nodeU()/nodeV() if you don't.";
  static final String EDGE_ALREADY_EXISTS = "Edge %s already exists in the graph.";
  static final String ENDPOINTS_MISMATCH =
      "Mismatch: endpoints' ordering is not compatible with directionality of the graph";

  /** Singleton edge value for {@link Graph} implementations backed by {@link ValueGraph}s. */
  enum Presence {
    EDGE_EXISTS
  }

import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.graph.GraphConstants.EDGE_REMOVED_FROM_GRAPH;
import static com.google.common.graph.GraphConstants.ENDPOINTS_MISMATCH;
import static com.google.common.graph.GraphConstants.MULTIPLE_EDGES_CONNECTING;
import static com.google.common.graph.GraphConstants.NODE_PAIR_REMOVED_FROM_GRAPH;

   *         <li>and {@link AbstractInvocationHandler#equals} returns true for the {@link
   *             InvocationHandler} of {@code argument}
   *       </ul>
   *   <li>other method calls are dispatched to {@link #handleInvocation}.
   * </ul>
   */
  @Override
  @CheckForNull
  public final Object invoke(Object proxy, Method method, @CheckForNull @Nullable Object[] args)
      throws Throwable {