content: /*
   * Copyright (c) 2015, 2020, Oracle and/or its affiliates.
   *
   * This program is free software; you can redistribute it and/or modify it under
   * the terms of the GNU General Public License, version 2.0, as published by the
   * Free Software Foundation.
   *
   * This program is also distributed with certain software (including but not
   * limited to OpenSSL) that is licensed under separate terms, as designated in a
   * particular file or component or in included license documentation. The
   * authors of MySQL hereby grant you an additional permission to link the
   * program and your derivative works with the separately licensed software that
   * they have included with MySQL.
   *
   * Without limiting anything contained in the foregoing, this file, which is
   * part of MySQL Connector/J, is also subject to the Universal FOSS Exception,
   * version 1.0, a copy of which can be found at
   * http://oss.oracle.com/licenses/universal-foss-exception.
   *
   * This program is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
   * FOR A PARTICULAR PURPOSE. See the GNU General Public License, version 2.0,
   * for more details.
   *
   * You should have received a copy of the GNU General Public License along with
   * this program; if not, write to the Free Software Foundation, Inc.,
   * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
   */
  
  package com.mysql.cj.util;
  
  import java.util.function.Supplier;
  
  /**
   * A lazy string that can take a byte buffer and encoding and interpret it as a string if/when requested. The string is cached and saved for any further
   * requests. "NULL" values can be represented by a 0-len string or a <i>null</i> passed to LazyString(String).
   */
  public class LazyString implements Supplier<String> {
      private String string; // the string, if one has been created
      private byte[] buffer;
      private int offset;
      private int length;
      private String encoding;
  
      public LazyString(String string) {
          // convenience for wrapping
          this.string = string;
      }
  
      public LazyString(byte[] buffer, int offset, int length, String encoding) {
          this.buffer = buffer;
          this.offset = offset;
          this.length = length;
          this.encoding = encoding;
      }
  
      public LazyString(byte[] buffer, int offset, int length) {
          this.buffer = buffer;
          this.offset = offset;
          this.length = length;
      }
  
      private String createAndCacheString() {
          if (this.length > 0) {
              this.string = this.encoding == null ? StringUtils.toString(this.buffer, this.offset, this.length)
                      : StringUtils.toString(this.buffer, this.offset, this.length, this.encoding);
          }
          // this can be NULL for 0-len strings
          return this.string;
      }
  
      @Override
      public String toString() {
          if (this.string != null) {
              return this.string;
          }
          return createAndCacheString();
      }
  
      public int length() {
          if (this.string != null) {
              return this.string.length();
          }
          return this.length;
      }
  
      @Override
      public String get() {
          return toString();
      }
  }
  