content: /*
   * Copyright (C) 2016-2023 ActionTech.
   * License: http://www.gnu.org/licenses/gpl.html GPL version 2 or higher.
   */
  
  /**
   *
   */
  package com.actiontech.dble.plan.common.item.function.mathsfunc;
  
  import com.actiontech.dble.plan.common.item.Item;
  import com.actiontech.dble.plan.common.item.function.ItemFunc;
  import com.actiontech.dble.plan.common.item.function.primary.ItemIntFunc;
  
  import java.math.BigInteger;
  import java.util.List;
  import java.util.zip.CRC32;
  
  public class ItemFuncCrc32 extends ItemIntFunc {
  
      /**
       * @param a
       */
      public ItemFuncCrc32(Item a, int charsetIndex) {
          super(a, charsetIndex);
      }
  
      @Override
      public final String funcName() {
          return "crc32";
      }
  
      @Override
      public void fixLengthAndDec() {
          maxLength = 10;
      }
  
      @Override
      public BigInteger valInt() {
          String res = args.get(0).valStr();
          if (res == null) {
              nullValue = true;
              return BigInteger.ZERO;
          }
          nullValue = false;
          CRC32 crc = new CRC32();
          crc.update(res.getBytes());
          return BigInteger.valueOf(crc.getValue());
      }
  
      @Override
      public ItemFunc nativeConstruct(List<Item> realArgs) {
          return new ItemFuncCrc32(realArgs.get(0), charsetIndex);
      }
  }
  