content: /*
  3 * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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 org.apache.asterix.lang.common.struct;
  
  import java.util.Arrays;
  import java.util.Optional;
  
  public enum UnaryExprType {
      POSITIVE("+"),
      NEGATIVE("-"),
      EXISTS("exists"),
      NOT_EXISTS("not_exists");
  
      private final String symbol;
  
      UnaryExprType(String s) {
          symbol = s;
      }
  
      @Override
      public String toString() {
          return symbol;
      }
  
      public static Optional<UnaryExprType> fromSymbol(String symbol) {
          return Arrays.stream(UnaryExprType.values()).filter(o -> o.symbol.equals(symbol)).findFirst();
      }
  }
  