content: /*
   * Copyright (C) 2008 The Android Open Source Project
   *
   * Licensed 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 android.text.util;
  
  import android.annotation.Nullable;
  
  /**
   * This class stores an RFC 822-like name, address, and comment,
   * and provides methods to convert them to quoted strings.
   */
  public class Rfc822Token {
      @Nullable
      private String mName, mAddress, mComment;
  
      /**
       * Creates a new Rfc822Token with the specified name, address,
       * and comment.
       */
      public Rfc822Token(@Nullable String name, @Nullable String address, @Nullable String comment) {
          mName = name;
          mAddress = address;
          mComment = comment;
      }
  
      /**
       * Returns the name part.
       */
      @Nullable
      public String getName() {
          return mName;
      }
  
      /**
       * Returns the address part.
       */
      @Nullable
      public String getAddress() {
          return mAddress;
      }
  
      /**
       * Returns the comment part.
       */
      @Nullable
      public String getComment() {
          return mComment;
      }
  
      /**
       * Changes the name to the specified name.
       */
      public void setName(@Nullable String name) {
          mName = name;
      }
  
      /**
       * Changes the address to the specified address.
       */
      public void setAddress(@Nullable String address) {
          mAddress = address;
      }
  
      /**
       * Changes the comment to the specified comment.
       */
      public void setComment(@Nullable String comment) {
          mComment = comment;
      }
  
      /**
       * Returns the name (with quoting added if necessary),
       * the comment (in parentheses), and the address (in angle brackets).
       * This should be suitable for inclusion in an RFC 822 address list.
       */
      public String toString() {
          StringBuilder sb = new StringBuilder();
  
          if (mName != null && mName.length() != 0) {
              sb.append(quoteNameIfNecessary(mName));
              sb.append(' ');
          }
  
          if (mComment != null && mComment.length() != 0) {
              sb.append('(');
              sb.append(quoteComment(mComment));
              sb.append(") ");
          }
  
          if (mAddress != null && mAddress.length() != 0) {
              sb.append('<');
              sb.append(mAddress);
              sb.append('>');
          }
  
          return sb.toString();
      }
  
      /**
       * Returns the name, conservatively quoting it if there are any
       * characters that are likely to cause trouble outside of a
       * quoted string, or returning it literally if it seems safe.
       */
      public static String quoteNameIfNecessary(String name) {
          int len = name.length();
  
          for (int i = 0; i < len; i++) {
              char c = name.charAt(i);
  
              if (! ((c >= 'A' && c <= 'Z') ||
                     (c >= 'a' && c <= 'z') ||
                     (c == ' ') ||
                     (c >= '0' && c <= '9'))) {
                  return '"' + quoteName(name) + '"';
              }
          }
  
          return name;
      }
  
      /**
       * Returns the name, with internal backslashes and quotation marks
       * preceded by backslashes.  The outer quote marks themselves are not
       * added by this method.
       */
      public static String quoteName(String name) {
          StringBuilder sb = new StringBuilder();
  
          int len = name.length();
          for (int i = 0; i < len; i++) {
              char c = name.charAt(i);
  
              if (c == '\\' || c == '"') {
                  sb.append('\\');
              }
  
              sb.append(c);
          }
  
          return sb.toString();
      }
  
      /**
       * Returns the comment, with internal backslashes and parentheses
       * preceded by backslashes.  The outer parentheses themselves are
       * not added by this method.
       */
      public static String quoteComment(String comment) {
          int len = comment.length();
          StringBuilder sb = new StringBuilder();
  
          for (int i = 0; i < len; i++) {
              char c = comment.charAt(i);
  
              if (c == '(' || c == ')' || c == '\\') {
                  sb.append('\\');
              }
  
              sb.append(c);
          }
  
          return sb.toString();
      }
  
      public int hashCode() {
          int result = 17;
          if (mName != null) result = 31 * result + mName.hashCode();
          if (mAddress != null) result = 31 * result + mAddress.hashCode();
          if (mComment != null) result = 31 * result + mComment.hashCode();
          return result;
      }
  
      private static boolean stringEquals(String a, String b) {
          if (a == null) {
              return (b == null);
          } else {
              return (a.equals(b));
          }
      }
  
      public boolean equals(Object o) {
          if (!(o instanceof Rfc822Token)) {
              return false;
          }
          Rfc822Token other = (Rfc822Token) o;
          return (stringEquals(mName, other.mName) &&
                  stringEquals(mAddress, other.mAddress) &&
                  stringEquals(mComment, other.mComment));
      }
  }
  
  