src/com/android/messaging/util/EmailAddress.java - platform/packages/apps/Messaging - Git at Google

 /*
  * Copyright (C) 2015 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 com.android.messaging.util;

 import com.google.common.base.CharMatcher;

 /**
  * Parsing the email address
  */
 public final class EmailAddress {
     private static final CharMatcher ANY_WHITESPACE = CharMatcher.anyOf(
             " \t\n\r\f\u000B\u0085\u2028\u2029\u200D\uFFEF\uFFFD\uFFFE\uFFFF");
     private static final CharMatcher EMAIL_ALLOWED_CHARS = CharMatcher.inRange((char) 0, (char) 31)
             .or(CharMatcher.is((char) 127))
             .or(CharMatcher.anyOf(" @,:<>"))
             .negate();

     /**
      * Helper method that checks whether the input text is valid email address.
      * TODO: This creates a new EmailAddress object each time
      * Need to make it more lightweight by pulling out the validation code into a static method.
      */
     public static boolean isValidEmail(final String emailText) {
         return new EmailAddress(emailText).isValid();
     }

     /**
      * Parses the specified email address. Internationalized addresses are treated as invalid.
      *
      * @param emailString A string representing just an email address. It should
      * not contain any other tokens. <code>"Name&lt;foo@example.org>"</code> won't be valid.
      */
     public EmailAddress(final String emailString) {
         this(emailString, false);
     }

     /**
      * Parses the specified email address.
      *
      * @param emailString A string representing just an email address. It should
      * not contain any other tokens. <code>"Name&lt;foo@example.org>"</code> won't be valid.
      * @param i18n Accept an internationalized address if it is true.
      */
     public EmailAddress(final String emailString, final boolean i18n) {
         allowI18n = i18n;
         valid = parseEmail(emailString);
     }

     /**
      * Parses the specified email address. Internationalized addresses are treated as invalid.
      *
      * @param user A string representing the username in the email prior to the '@' symbol
      * @param host A string representing the host following the '@' symbol
      */
     public EmailAddress(final String user, final String host) {
         this(user, host, false);
     }

     /**
      * Parses the specified email address.
      *
      * @param user A string representing the username in the email prior to the '@' symbol
      * @param host A string representing the host following the '@' symbol
      * @param i18n Accept an internationalized address if it is true.
      */
     public EmailAddress(final String user, final String host, final boolean i18n) {
         allowI18n = i18n;
         this.user = user;
         setHost(host);
     }

     protected boolean parseEmail(final String emailString) {
         // check for null
         if (emailString == null) {
             return false;
         }

         // Check for an '@' character. Get the last one, in case the local part is
         // quoted. See http://b/1944742.
         final int atIndex = emailString.lastIndexOf('@');
         if ((atIndex <= 0) || // no '@' character in the email address
                               // or @ on the first position
                 (atIndex == (emailString.length() - 1))) { // last character, no host
             return false;
         }

         user = emailString.substring(0, atIndex);
         host = emailString.substring(atIndex + 1);

         return isValidInternal();
     }

     @Override
     public String toString() {
         return user + "@" + host;
     }

     /**
      * Ensure the email address is valid, conforming to current RFC2821 and
      * RFC2822 guidelines (although some iffy characters, like ! and ;, are
      * allowed because they are not technically prohibited in the RFC)
      */
     private boolean isValidInternal() {
         if ((user == null) || (host == null)) {
             return false;
         }

         if ((user.length() == 0) || (host.length() == 0)) {
             return false;
         }

         // check for white space in the host
         if (ANY_WHITESPACE.indexIn(host) >= 0) {
             return false;
         }

         // ensure the host is above the minimum length
         if (host.length() < 4) {
             return false;
         }

         final int firstDot = host.indexOf('.');

         // ensure host contains at least one dot
         if (firstDot == -1) {
             return false;
         }

         // check if the host contains two continuous dots.
         if (host.indexOf("..") >= 0) {
             return false;
         }

         // check if the first host char is a dot.
         if (host.charAt(0) == '.') {
             return false;
         }

         final int secondDot = host.indexOf(".", firstDot + 1);

         // if there's a dot at the end, there needs to be a second dot
         if (host.charAt(host.length() - 1) == '.' && secondDot == -1) {
             return false;
         }

         // Host must not have any disallowed characters; allowI18n dictates whether
         // host must be ASCII.
         if (!EMAIL_ALLOWED_CHARS.matchesAllOf(host)
                 || (!allowI18n && !CharMatcher.ASCII.matchesAllOf(host))) {
             return false;
         }

         if (user.startsWith("\"")) {
             if (!isQuotedUserValid()) {
                 return false;
             }
         } else {
             // check for white space in the user
             if (ANY_WHITESPACE.indexIn(user) >= 0) {
                 return false;
             }

             // the user cannot contain two continuous dots
             if (user.indexOf("..") >= 0) {
                 return false;
             }

             // User must not have any disallowed characters; allow I18n dictates whether
             // user must be ASCII.
             if (!EMAIL_ALLOWED_CHARS.matchesAllOf(user)
                     || (!allowI18n && !CharMatcher.ASCII.matchesAllOf(user))) {
                 return false;
             }
         }
         return true;
     }

     private boolean isQuotedUserValid() {
         final int limit = user.length() - 1;
         if (limit < 1 || !user.endsWith("\"")) {
             return false;
         }

         // Unusual loop bounds (looking only at characters between the outer quotes,
         // not at either quote character). Plus, i is manipulated within the loop.
         for (int i = 1; i < limit; ++i) {
             final char ch = user.charAt(i);
             if (ch == '"' || ch == 127
                     // No non-whitespace control chars:
                     || (ch < 32 && !ANY_WHITESPACE.matches(ch))
                     // No non-ASCII chars, unless i18n is in effect:
                     || (ch >= 128 && !allowI18n)) {
                 return false;
             } else if (ch == '\\') {
                 if (i + 1 < limit) {
                     ++i; // Skip the quoted character
                 } else {
                     // We have a trailing backslash -- so it can't be quoting anything.
                     return false;
                 }
             }
         }

         return true;
     }

     @Override
     public boolean equals(final Object otherObject) {
         // Do an instance check first as an optimization.
         if (this == otherObject) {
             return true;
         }
         if (otherObject instanceof EmailAddress) {
             final EmailAddress otherAddress = (EmailAddress) otherObject;
             return toString().equals(otherAddress.toString());
         }
         return false;
     }

     @Override
     public int hashCode() {
         // Arbitrary hash code as a function of both host and user.
         return toString().hashCode();
     }

     // accessors
     public boolean isValid() {
         return valid;
     }

     public String getUser() {
         return user;
     }

     public String getHost() {
         return host;
     }

     // used to change the host on an email address and rechecks validity

     /**
      * Changes the host name of the email address and rechecks the address'
      * validity. Exercise caution when storing EmailAddress instances in
      * hash-keyed collections. Calling setHost() with a different host name will
      * change the return value of hashCode.
      *
      * @param hostName The new host name of the email address.
      */
     public void setHost(final String hostName) {
         host = hostName;
         valid = isValidInternal();
     }

     protected boolean valid = false;
     protected String user = null;
     protected String host = null;
     protected boolean allowI18n = false;
 }
	/*
	* Copyright (C) 2015 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 com.android.messaging.util;

	import com.google.common.base.CharMatcher;

	/**
	* Parsing the email address
	*/
	public final class EmailAddress {
	private static final CharMatcher ANY_WHITESPACE = CharMatcher.anyOf(
	" \t\n\r\f\u000B\u0085\u2028\u2029\u200D\uFFEF\uFFFD\uFFFE\uFFFF");
	private static final CharMatcher EMAIL_ALLOWED_CHARS = CharMatcher.inRange((char) 0, (char) 31)
	.or(CharMatcher.is((char) 127))
	.or(CharMatcher.anyOf(" @,:<>"))
	.negate();

	/**
	* Helper method that checks whether the input text is valid email address.
	* TODO: This creates a new EmailAddress object each time
	* Need to make it more lightweight by pulling out the validation code into a static method.
	*/
	public static boolean isValidEmail(final String emailText) {
	return new EmailAddress(emailText).isValid();
	}

	/**
	* Parses the specified email address. Internationalized addresses are treated as invalid.
	*
	* @param emailString A string representing just an email address. It should
	* not contain any other tokens. <code>"Name<foo@example.org>"</code> won't be valid.
	*/
	public EmailAddress(final String emailString) {
	this(emailString, false);
	}

	/**
	* Parses the specified email address.
	*
	* @param emailString A string representing just an email address. It should
	* not contain any other tokens. <code>"Name<foo@example.org>"</code> won't be valid.
	* @param i18n Accept an internationalized address if it is true.
	*/
	public EmailAddress(final String emailString, final boolean i18n) {
	allowI18n = i18n;
	valid = parseEmail(emailString);
	}

	/**
	* Parses the specified email address. Internationalized addresses are treated as invalid.
	*
	* @param user A string representing the username in the email prior to the '@' symbol
	* @param host A string representing the host following the '@' symbol
	*/
	public EmailAddress(final String user, final String host) {
	this(user, host, false);
	}

	/**
	* Parses the specified email address.
	*
	* @param user A string representing the username in the email prior to the '@' symbol
	* @param host A string representing the host following the '@' symbol
	* @param i18n Accept an internationalized address if it is true.
	*/
	public EmailAddress(final String user, final String host, final boolean i18n) {
	allowI18n = i18n;
	this.user = user;
	setHost(host);
	}

	protected boolean parseEmail(final String emailString) {
	// check for null
	if (emailString == null) {
	return false;
	}

	// Check for an '@' character. Get the last one, in case the local part is
	// quoted. See http://b/1944742.
	final int atIndex = emailString.lastIndexOf('@');
	if ((atIndex <= 0) \|\| // no '@' character in the email address
	// or @ on the first position
	(atIndex == (emailString.length() - 1))) { // last character, no host
	return false;
	}

	user = emailString.substring(0, atIndex);
	host = emailString.substring(atIndex + 1);

	return isValidInternal();
	}

	@Override
	public String toString() {
	return user + "@" + host;
	}

	/**
	* Ensure the email address is valid, conforming to current RFC2821 and
	* RFC2822 guidelines (although some iffy characters, like ! and ;, are
	* allowed because they are not technically prohibited in the RFC)
	*/
	private boolean isValidInternal() {
	if ((user == null) \|\| (host == null)) {
	return false;
	}

	if ((user.length() == 0) \|\| (host.length() == 0)) {
	return false;
	}

	// check for white space in the host
	if (ANY_WHITESPACE.indexIn(host) >= 0) {
	return false;
	}

	// ensure the host is above the minimum length
	if (host.length() < 4) {
	return false;
	}

	final int firstDot = host.indexOf('.');

	// ensure host contains at least one dot
	if (firstDot == -1) {
	return false;
	}

	// check if the host contains two continuous dots.
	if (host.indexOf("..") >= 0) {
	return false;
	}

	// check if the first host char is a dot.
	if (host.charAt(0) == '.') {
	return false;
	}

	final int secondDot = host.indexOf(".", firstDot + 1);

	// if there's a dot at the end, there needs to be a second dot
	if (host.charAt(host.length() - 1) == '.' && secondDot == -1) {
	return false;
	}

	// Host must not have any disallowed characters; allowI18n dictates whether
	// host must be ASCII.
	if (!EMAIL_ALLOWED_CHARS.matchesAllOf(host)
	\|\| (!allowI18n && !CharMatcher.ASCII.matchesAllOf(host))) {
	return false;
	}

	if (user.startsWith("\"")) {
	if (!isQuotedUserValid()) {
	return false;
	}
	} else {
	// check for white space in the user
	if (ANY_WHITESPACE.indexIn(user) >= 0) {
	return false;
	}

	// the user cannot contain two continuous dots
	if (user.indexOf("..") >= 0) {
	return false;
	}

	// User must not have any disallowed characters; allow I18n dictates whether
	// user must be ASCII.
	if (!EMAIL_ALLOWED_CHARS.matchesAllOf(user)
	\|\| (!allowI18n && !CharMatcher.ASCII.matchesAllOf(user))) {
	return false;
	}
	}
	return true;
	}

	private boolean isQuotedUserValid() {
	final int limit = user.length() - 1;
	if (limit < 1 \|\| !user.endsWith("\"")) {
	return false;
	}

	// Unusual loop bounds (looking only at characters between the outer quotes,
	// not at either quote character). Plus, i is manipulated within the loop.
	for (int i = 1; i < limit; ++i) {
	final char ch = user.charAt(i);
	if (ch == '"' \|\| ch == 127
	// No non-whitespace control chars:
	\|\| (ch < 32 && !ANY_WHITESPACE.matches(ch))
	// No non-ASCII chars, unless i18n is in effect:
	\|\| (ch >= 128 && !allowI18n)) {
	return false;
	} else if (ch == '\\') {
	if (i + 1 < limit) {
	++i; // Skip the quoted character
	} else {
	// We have a trailing backslash -- so it can't be quoting anything.
	return false;
	}
	}
	}

	return true;
	}

	@Override
	public boolean equals(final Object otherObject) {
	// Do an instance check first as an optimization.
	if (this == otherObject) {
	return true;
	}
	if (otherObject instanceof EmailAddress) {
	final EmailAddress otherAddress = (EmailAddress) otherObject;
	return toString().equals(otherAddress.toString());
	}
	return false;
	}

	@Override
	public int hashCode() {
	// Arbitrary hash code as a function of both host and user.
	return toString().hashCode();
	}

	// accessors
	public boolean isValid() {
	return valid;
	}

	public String getUser() {
	return user;
	}

	public String getHost() {
	return host;
	}

	// used to change the host on an email address and rechecks validity

	/**
	* Changes the host name of the email address and rechecks the address'
	* validity. Exercise caution when storing EmailAddress instances in
	* hash-keyed collections. Calling setHost() with a different host name will
	* change the return value of hashCode.
	*
	* @param hostName The new host name of the email address.
	*/
	public void setHost(final String hostName) {
	host = hostName;
	valid = isValidInternal();
	}

	protected boolean valid = false;
	protected String user = null;
	protected String host = null;
	protected boolean allowI18n = false;
	}