java/src/com/google/i18n/phonenumbers/AsYouTypeFormatter.java - platform/external/libphonenumber - Git at Google

 /*
  * Copyright (C) 2009 Google Inc.
  *
  * 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.google.i18n.phonenumbers;

 import com.google.i18n.phonenumbers.Phonemetadata.NumberFormat;
 import com.google.i18n.phonenumbers.Phonemetadata.PhoneMetadata;

 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;

 /**
  * A formatter which formats phone numbers as they are entered.
  *
  * An AsYouTypeFormatter could be created by invoking the getAsYouTypeFormatter method of the
  * PhoneNumberUtil. After that digits could be added by invoking the inputDigit method on the
  * formatter instance, and the partially formatted phone number will be returned each time a digit
  * is added. The clear method could be invoked before a new number needs to be formatted.
  *
  * See testAsYouTypeFormatterUS(), testAsYouTestFormatterGB() and testAsYouTypeFormatterDE() in
  * PhoneNumberUtilTest.java for more details on how the formatter is to be used.
  *
  * @author Shaopeng Jia
  */
 public class AsYouTypeFormatter {
   private String currentOutput = "";
   private StringBuffer formattingTemplate = new StringBuffer();
   // The pattern from numberFormat that is currently used to create formattingTemplate.
   private String currentFormattingPattern = "";
   private StringBuffer accruedInput = new StringBuffer();
   private StringBuffer accruedInputWithoutFormatting = new StringBuffer();
   private boolean ableToFormat = true;
   private boolean isInternationalFormatting = false;
   private boolean isExpectingCountryCode = false;
   private final PhoneNumberUtil phoneUtil = PhoneNumberUtil.getInstance();
   private String defaultCountry;
   private PhoneMetadata defaultMetaData;
   private PhoneMetadata currentMetaData;

   // A pattern that is used to match character classes in regular expressions. An example of a
   // character class is [1-4].
   private final Pattern CHARACTER_CLASS_PATTERN = Pattern.compile("\\[([^\\[\\]])*\\]");
   // Any digit in a regular expression that actually denotes a digit. For example, in the regular
   // expression 80[0-2]\d{6,10}, the first 2 digits (8 and 0) are standalone digits, but the rest
   // are not.
   // Two look-aheads are needed because the number following \\d could be a two-digit number, since
   // the phone number can be as long as 15 digits.
   private static final Pattern STANDALONE_DIGIT_PATTERN = Pattern.compile("\\d(?=[^,}][^,}])");

   // This is the minimum length of national number accrued that is required to trigger the
   // formatter. The first element of the leadingDigitsPattern of each numberFormat contains a
   // regular expression that matches up to this number of digits.
   private static final int MIN_LEADING_DIGITS_LENGTH = 3;

   // The digits that have not been entered yet will be represented by a \u2008, the punctuation
   // space.
   private String digitPlaceholder = "\u2008";
   private Pattern digitPattern = Pattern.compile(digitPlaceholder);
   private int lastMatchPosition = 0;
   // The position of a digit upon which inputDigitAndRememberPosition is most recently invoked, as
   // found in the original sequence of characters the user entered.
   private int originalPosition = 0;
   // The position of a digit upon which inputDigitAndRememberPosition is most recently invoked, as
   // found in accruedInputWithoutFormatting.
   private int positionToRemember = 0;
   private Pattern nationalPrefixForParsing;
   private Pattern internationalPrefix;
   private StringBuffer prefixBeforeNationalNumber = new StringBuffer();
   private StringBuffer nationalNumber = new StringBuffer();
   private List<NumberFormat> possibleFormats = new ArrayList<NumberFormat>();

     // A cache for frequently used country-specific regular expressions.
   private RegexCache regexCache = new RegexCache(64);

   /**
    * Constructs a light-weight formatter which does no formatting, but outputs exactly what is
    * fed into the inputDigit method.
    *
    * @param regionCode  the country/region where the phone number is being entered
    */
   AsYouTypeFormatter(String regionCode) {
     defaultCountry = regionCode;
     initializeCountrySpecificInfo(defaultCountry);
     defaultMetaData = currentMetaData;
   }

   private void initializeCountrySpecificInfo(String regionCode) {
     currentMetaData = phoneUtil.getMetadataForRegion(regionCode);
     nationalPrefixForParsing =
         regexCache.getPatternForRegex(currentMetaData.getNationalPrefixForParsing());
     internationalPrefix =
         regexCache.getPatternForRegex("\\+|" + currentMetaData.getInternationalPrefix());
   }

   // Returns true if a new template is created as opposed to reusing the existing template.
   private boolean maybeCreateNewTemplate() {
     // When there are multiple available formats, the formatter uses the first format where a
     // formatting template could be created.
     for (NumberFormat numberFormat : possibleFormats) {
       String pattern = numberFormat.getPattern();
       if (currentFormattingPattern.equals(pattern)) {
         return false;
       }
       if (createFormattingTemplate(numberFormat)) {
         currentFormattingPattern = pattern;
         return true;
       }
     }
     ableToFormat = false;
     return false;
   }

   private void getAvailableFormats(String leadingThreeDigits) {
     List<NumberFormat> formatList =
         (isInternationalFormatting && currentMetaData.getIntlNumberFormatCount() > 0)
         ? currentMetaData.getIntlNumberFormatList()
         : currentMetaData.getNumberFormatList();
     possibleFormats.addAll(formatList);
     narrowDownPossibleFormats(leadingThreeDigits);
   }

   private void narrowDownPossibleFormats(String leadingDigits) {
     int lengthOfLeadingDigits = leadingDigits.length();
     int indexOfLeadingDigitsPattern = lengthOfLeadingDigits - MIN_LEADING_DIGITS_LENGTH;
     Iterator<NumberFormat> it = possibleFormats.iterator();
     while (it.hasNext()) {
       NumberFormat format = it.next();
       if (format.getLeadingDigitsPatternCount() > indexOfLeadingDigitsPattern) {
         Pattern leadingDigitsPattern =
             regexCache.getPatternForRegex(
                 format.getLeadingDigitsPattern(indexOfLeadingDigitsPattern));
         Matcher m = leadingDigitsPattern.matcher(leadingDigits);
         if (!m.lookingAt()) {
           it.remove();
         }
       } // else the particular format has no more specific leadingDigitsPattern, and it should be
         // retained.
     }
   }

   private boolean createFormattingTemplate(NumberFormat format) {
     String numberFormat = format.getFormat();
     String numberPattern = format.getPattern();

     // The formatter doesn't format numbers when numberPattern contains "|", e.g.
     // (20|3)\d{4}. In those cases we quickly return.
     if (numberPattern.indexOf('|') != -1) {
       return false;
     }

     // Replace anything in the form of [..] with \d
     numberPattern = CHARACTER_CLASS_PATTERN.matcher(numberPattern).replaceAll("\\\\d");

     // Replace any standalone digit (not the one in d{}) with \d
     numberPattern = STANDALONE_DIGIT_PATTERN.matcher(numberPattern).replaceAll("\\\\d");
     formattingTemplate.setLength(0);
     formattingTemplate.append(getFormattingTemplate(numberPattern, numberFormat));
     return true;
   }

   // Gets a formatting template which could be used to efficiently format a partial number where
   // digits are added one by one.
   private String getFormattingTemplate(String numberPattern, String numberFormat) {
     // Creates a phone number consisting only of the digit 9 that matches the
     // numberPattern by applying the pattern to the longestPhoneNumber string.
     String longestPhoneNumber = "999999999999999";
     Matcher m = regexCache.getPatternForRegex(numberPattern).matcher(longestPhoneNumber);
     m.find();  // this will always succeed
     String aPhoneNumber = m.group();
     // Formats the number according to numberFormat
     String template = aPhoneNumber.replaceAll(numberPattern, numberFormat);
     // Replaces each digit with character digitPlaceholder
     template = template.replaceAll("9", digitPlaceholder);
     return template;
   }

   /**
    * Clears the internal state of the formatter, so it could be reused.
    */
   public void clear() {
     currentOutput = "";
     accruedInput.setLength(0);
     accruedInputWithoutFormatting.setLength(0);
     formattingTemplate.setLength(0);
     lastMatchPosition = 0;
     currentFormattingPattern = "";
     prefixBeforeNationalNumber.setLength(0);
     nationalNumber.setLength(0);
     ableToFormat = true;
     positionToRemember = 0;
     originalPosition = 0;
     isInternationalFormatting = false;
     isExpectingCountryCode = false;
     possibleFormats.clear();
     if (!currentMetaData.equals(defaultMetaData)) {
       initializeCountrySpecificInfo(defaultCountry);
     }
   }

   /**
    * Formats a phone number on-the-fly as each digit is entered.
    *
    * @param nextChar  the most recently entered digit of a phone number. Formatting characters are
    *     allowed, but they are removed from the result. Full width digits and Arabic-indic digits
    *     are allowed, and will be shown as they are.
    * @return  the partially formatted phone number.
    */
   public String inputDigit(char nextChar) {
     currentOutput = inputDigitWithOptionToRememberPosition(nextChar, false);
     return currentOutput;
   }

   /**
    * Same as inputDigit, but remembers the position where nextChar is inserted, so that it could be
    * retrieved later by using getRememberedPosition(). The remembered position will be automatically
    * adjusted if additional formatting characters are later inserted/removed in front of nextChar.
    */
   public String inputDigitAndRememberPosition(char nextChar) {
     currentOutput = inputDigitWithOptionToRememberPosition(nextChar, true);
     return currentOutput;
   }

   @SuppressWarnings(value = "fallthrough")
   private String inputDigitWithOptionToRememberPosition(char nextChar, boolean rememberPosition) {
     accruedInput.append(nextChar);
     if (rememberPosition) {
       originalPosition = accruedInput.length();
     }
     // We do formatting on-the-fly only when each character entered is either a plus sign or a
     // digit.
     if (!PhoneNumberUtil.VALID_START_CHAR_PATTERN.matcher(Character.toString(nextChar)).matches()) {
       ableToFormat = false;
     }
     if (!ableToFormat) {
       return accruedInput.toString();
     }

     nextChar = normalizeAndAccrueDigitsAndPlusSign(nextChar, rememberPosition);

     // We start to attempt to format only when at least MIN_LEADING_DIGITS_LENGTH digits (the plus
     // sign is counted as a digit as well for this purpose) have been entered.
     switch (accruedInputWithoutFormatting.length()) {
       case 0: // this is the case where the first few inputs are neither digits nor the plus sign.
       case 1:
       case 2:
         return accruedInput.toString();
       case 3:
         if (attemptToExtractIdd()) {
           isExpectingCountryCode = true;
         } else {  // No IDD or plus sign is found, must be entering in national format.
           removeNationalPrefixFromNationalNumber();
           return attemptToChooseFormattingPattern();
         }
       case 4:
       case 5:
         if (isExpectingCountryCode) {
           if (attemptToExtractCountryCode()) {
             isExpectingCountryCode = false;
           }
           return prefixBeforeNationalNumber + nationalNumber.toString();
         }
       // We make a last attempt to extract a country code at the 6th digit because the maximum
       // length of IDD and country code are both 3.
       case 6:
         if (isExpectingCountryCode && !attemptToExtractCountryCode()) {
           ableToFormat = false;
           return accruedInput.toString();
         }
       default:
         if (possibleFormats.size() > 0) {  // The formatting pattern is already chosen.
           String tempNationalNumber = inputDigitHelper(nextChar);
           // See if the accrued digits can be formatted properly already. If not, use the results
           // from inputDigitHelper, which does formatting based on the formatting pattern chosen.
           String formattedNumber = attemptToFormatAccruedDigits();
           if (formattedNumber.length() > 0) {
             return formattedNumber;
           }
           narrowDownPossibleFormats(nationalNumber.toString());
           if (maybeCreateNewTemplate()) {
             return inputAccruedNationalNumber();
           }
           return ableToFormat
              ? prefixBeforeNationalNumber + tempNationalNumber
              : tempNationalNumber;
         } else {
           return attemptToChooseFormattingPattern();
         }
     }
   }

   String attemptToFormatAccruedDigits() {
     for (NumberFormat numFormat : possibleFormats) {
       Matcher m = regexCache.getPatternForRegex(numFormat.getPattern()).matcher(nationalNumber);
       if (m.matches()) {
         String formattedNumber = m.replaceAll(numFormat.getFormat());
         return prefixBeforeNationalNumber + formattedNumber;
       }
     }
     return "";
   }

   /**
    * Returns the current position in the partially formatted phone number of the character which was
    * previously passed in as the parameter of inputDigitAndRememberPosition().
    */
   public int getRememberedPosition() {
     if (!ableToFormat) {
       return originalPosition;
     }
     int accruedInputIndex = 0, currentOutputIndex = 0;
     while (accruedInputIndex < positionToRemember) {
       if (accruedInputWithoutFormatting.charAt(accruedInputIndex) ==
           currentOutput.charAt(currentOutputIndex)) {
         accruedInputIndex++;
         currentOutputIndex++;
       } else {
         currentOutputIndex++;
       }
     }
     return currentOutputIndex;
   }

   // Attempts to set the formatting template and returns a string which contains the formatted
   // version of the digits entered so far.
   private String attemptToChooseFormattingPattern() {
     // We start to attempt to format only when as least MIN_LEADING_DIGITS_LENGTH digits of national
     // number (excluding national prefix) have been entered.
     if (nationalNumber.length() >= MIN_LEADING_DIGITS_LENGTH) {
       getAvailableFormats(nationalNumber.substring(0, MIN_LEADING_DIGITS_LENGTH));
       maybeCreateNewTemplate();
       return inputAccruedNationalNumber();
     } else {
       return prefixBeforeNationalNumber + nationalNumber.toString();
     }
   }

   // Invokes inputDigitHelper on each digit of the national number accrued, and returns a formatted
   // string in the end.
   private String inputAccruedNationalNumber() {
     int lengthOfNationalNumber = nationalNumber.length();
     if (lengthOfNationalNumber > 0) {
       String tempNationalNumber = "";
       for (int i = 0; i < lengthOfNationalNumber; i++) {
         tempNationalNumber = inputDigitHelper(nationalNumber.charAt(i));
       }
       return ableToFormat
           ? prefixBeforeNationalNumber + tempNationalNumber
           : tempNationalNumber;
     } else {
       return prefixBeforeNationalNumber.toString();
     }
   }

   private void removeNationalPrefixFromNationalNumber() {
     int startOfNationalNumber = 0;
     if (currentMetaData.getCountryCode() == 1 && nationalNumber.charAt(0) == '1') {
       startOfNationalNumber = 1;
       prefixBeforeNationalNumber.append("1 ");
       isInternationalFormatting = true;
     } else if (currentMetaData.hasNationalPrefix()) {
       Matcher m = nationalPrefixForParsing.matcher(nationalNumber);
       if (m.lookingAt()) {
         startOfNationalNumber = m.end();
         prefixBeforeNationalNumber.append(nationalNumber.substring(0, startOfNationalNumber));
       }
     }
     nationalNumber.delete(0, startOfNationalNumber);
   }

   /**
    * Extracts IDD and plus sign to prefixBeforeNationalNumber when they are available, and places
    * the remaining input into nationalNumber.
    *
    * @return  true when accruedInputWithoutFormatting begins with the plus sign or valid IDD for
    *     defaultCountry.
    */
   private boolean attemptToExtractIdd() {
     Matcher iddMatcher = internationalPrefix.matcher(accruedInputWithoutFormatting);
     if (iddMatcher.lookingAt()) {
       isInternationalFormatting = true;
       int startOfCountryCode = iddMatcher.end();
       nationalNumber.setLength(0);
       nationalNumber.append(accruedInputWithoutFormatting.substring(startOfCountryCode));
       prefixBeforeNationalNumber.append(
           accruedInputWithoutFormatting.substring(0, startOfCountryCode));
       if (accruedInputWithoutFormatting.charAt(0) != PhoneNumberUtil.PLUS_SIGN) {
         prefixBeforeNationalNumber.append(" ");
       }
       return true;
     }
     return false;
   }

   /**
    * Extracts country code from the beginning of nationalNumber to prefixBeforeNationalNumber when
    * they are available, and places the remaining input into nationalNumber.
    *
    * @return  true when a valid country code can be found.
    */
   private boolean attemptToExtractCountryCode() {
       if (nationalNumber.length() == 0) {
         return false;
       }
       StringBuffer numberWithoutCountryCode = new StringBuffer();
       int countryCode = phoneUtil.extractCountryCode(nationalNumber, numberWithoutCountryCode);
       if (countryCode == 0) {
         return false;
       } else {
         nationalNumber.setLength(0);
         nationalNumber.append(numberWithoutCountryCode);
         String newRegionCode = phoneUtil.getRegionCodeForCountryCode(countryCode);
         if (!newRegionCode.equals(defaultCountry)) {
           initializeCountrySpecificInfo(newRegionCode);
         }
         String countryCodeString = Integer.toString(countryCode);
         prefixBeforeNationalNumber.append(countryCodeString).append(" ");
       }
     return true;
   }

   // Accrues digits and the plus sign to accruedInputWithoutFormatting for later use. If nextChar
   // contains a digit in non-ASCII format (e.g. the full-width version of digits), it is first
   // normalized to the ASCII version. The return value is nextChar itself, or its normalized
   // version, if nextChar is a digit in non-ASCII format.
   private char normalizeAndAccrueDigitsAndPlusSign(char nextChar, boolean rememberPosition) {
     if (nextChar == PhoneNumberUtil.PLUS_SIGN) {
       accruedInputWithoutFormatting.append(nextChar);
     }
     if (PhoneNumberUtil.DIGIT_MAPPINGS.containsKey(nextChar)) {
       nextChar = PhoneNumberUtil.DIGIT_MAPPINGS.get(nextChar);
       accruedInputWithoutFormatting.append(nextChar);
       nationalNumber.append(nextChar);
     }
     if (rememberPosition) {
       positionToRemember = accruedInputWithoutFormatting.length();
     }
     return nextChar;
   }

   private String inputDigitHelper(char nextChar) {
     Matcher digitMatcher = digitPattern.matcher(formattingTemplate);
     if (digitMatcher.find(lastMatchPosition)) {
       String tempTemplate = digitMatcher.replaceFirst(Character.toString(nextChar));
       formattingTemplate.replace(0, tempTemplate.length(), tempTemplate);
       lastMatchPosition = digitMatcher.start();
       return formattingTemplate.substring(0, lastMatchPosition + 1);
     } else {  // More digits are entered than we could handle.
       ableToFormat = false;
       return accruedInput.toString();
     }
   }
 }
	/*
	* Copyright (C) 2009 Google Inc.
	*
	* 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.google.i18n.phonenumbers;

	import com.google.i18n.phonenumbers.Phonemetadata.NumberFormat;
	import com.google.i18n.phonenumbers.Phonemetadata.PhoneMetadata;

	import java.util.ArrayList;
	import java.util.Iterator;
	import java.util.List;
	import java.util.regex.Matcher;
	import java.util.regex.Pattern;

	/**
	* A formatter which formats phone numbers as they are entered.
	*
	* An AsYouTypeFormatter could be created by invoking the getAsYouTypeFormatter method of the
	* PhoneNumberUtil. After that digits could be added by invoking the inputDigit method on the
	* formatter instance, and the partially formatted phone number will be returned each time a digit
	* is added. The clear method could be invoked before a new number needs to be formatted.
	*
	* See testAsYouTypeFormatterUS(), testAsYouTestFormatterGB() and testAsYouTypeFormatterDE() in
	* PhoneNumberUtilTest.java for more details on how the formatter is to be used.
	*
	* @author Shaopeng Jia
	*/
	public class AsYouTypeFormatter {
	private String currentOutput = "";
	private StringBuffer formattingTemplate = new StringBuffer();
	// The pattern from numberFormat that is currently used to create formattingTemplate.
	private String currentFormattingPattern = "";
	private StringBuffer accruedInput = new StringBuffer();
	private StringBuffer accruedInputWithoutFormatting = new StringBuffer();
	private boolean ableToFormat = true;
	private boolean isInternationalFormatting = false;
	private boolean isExpectingCountryCode = false;
	private final PhoneNumberUtil phoneUtil = PhoneNumberUtil.getInstance();
	private String defaultCountry;
	private PhoneMetadata defaultMetaData;
	private PhoneMetadata currentMetaData;

	// A pattern that is used to match character classes in regular expressions. An example of a
	// character class is [1-4].
	private final Pattern CHARACTER_CLASS_PATTERN = Pattern.compile("\\[([^\\[\\]])*\\]");
	// Any digit in a regular expression that actually denotes a digit. For example, in the regular
	// expression 80[0-2]\d{6,10}, the first 2 digits (8 and 0) are standalone digits, but the rest
	// are not.
	// Two look-aheads are needed because the number following \\d could be a two-digit number, since
	// the phone number can be as long as 15 digits.
	private static final Pattern STANDALONE_DIGIT_PATTERN = Pattern.compile("\\d(?=[^,}][^,}])");

	// This is the minimum length of national number accrued that is required to trigger the
	// formatter. The first element of the leadingDigitsPattern of each numberFormat contains a
	// regular expression that matches up to this number of digits.
	private static final int MIN_LEADING_DIGITS_LENGTH = 3;

	// The digits that have not been entered yet will be represented by a \u2008, the punctuation
	// space.
	private String digitPlaceholder = "\u2008";
	private Pattern digitPattern = Pattern.compile(digitPlaceholder);
	private int lastMatchPosition = 0;
	// The position of a digit upon which inputDigitAndRememberPosition is most recently invoked, as
	// found in the original sequence of characters the user entered.
	private int originalPosition = 0;
	// The position of a digit upon which inputDigitAndRememberPosition is most recently invoked, as
	// found in accruedInputWithoutFormatting.
	private int positionToRemember = 0;
	private Pattern nationalPrefixForParsing;
	private Pattern internationalPrefix;
	private StringBuffer prefixBeforeNationalNumber = new StringBuffer();
	private StringBuffer nationalNumber = new StringBuffer();
	private List<NumberFormat> possibleFormats = new ArrayList<NumberFormat>();

	// A cache for frequently used country-specific regular expressions.
	private RegexCache regexCache = new RegexCache(64);

	/**
	* Constructs a light-weight formatter which does no formatting, but outputs exactly what is
	* fed into the inputDigit method.
	*
	* @param regionCode the country/region where the phone number is being entered
	*/
	AsYouTypeFormatter(String regionCode) {
	defaultCountry = regionCode;
	initializeCountrySpecificInfo(defaultCountry);
	defaultMetaData = currentMetaData;
	}

	private void initializeCountrySpecificInfo(String regionCode) {
	currentMetaData = phoneUtil.getMetadataForRegion(regionCode);
	nationalPrefixForParsing =
	regexCache.getPatternForRegex(currentMetaData.getNationalPrefixForParsing());
	internationalPrefix =
	regexCache.getPatternForRegex("\\+\|" + currentMetaData.getInternationalPrefix());
	}

	// Returns true if a new template is created as opposed to reusing the existing template.
	private boolean maybeCreateNewTemplate() {
	// When there are multiple available formats, the formatter uses the first format where a
	// formatting template could be created.
	for (NumberFormat numberFormat : possibleFormats) {
	String pattern = numberFormat.getPattern();
	if (currentFormattingPattern.equals(pattern)) {
	return false;
	}
	if (createFormattingTemplate(numberFormat)) {
	currentFormattingPattern = pattern;
	return true;
	}
	}
	ableToFormat = false;
	return false;
	}

	private void getAvailableFormats(String leadingThreeDigits) {
	List<NumberFormat> formatList =
	(isInternationalFormatting && currentMetaData.getIntlNumberFormatCount() > 0)
	? currentMetaData.getIntlNumberFormatList()
	: currentMetaData.getNumberFormatList();
	possibleFormats.addAll(formatList);
	narrowDownPossibleFormats(leadingThreeDigits);
	}

	private void narrowDownPossibleFormats(String leadingDigits) {
	int lengthOfLeadingDigits = leadingDigits.length();
	int indexOfLeadingDigitsPattern = lengthOfLeadingDigits - MIN_LEADING_DIGITS_LENGTH;
	Iterator<NumberFormat> it = possibleFormats.iterator();
	while (it.hasNext()) {
	NumberFormat format = it.next();
	if (format.getLeadingDigitsPatternCount() > indexOfLeadingDigitsPattern) {
	Pattern leadingDigitsPattern =
	regexCache.getPatternForRegex(
	format.getLeadingDigitsPattern(indexOfLeadingDigitsPattern));
	Matcher m = leadingDigitsPattern.matcher(leadingDigits);
	if (!m.lookingAt()) {
	it.remove();
	}
	} // else the particular format has no more specific leadingDigitsPattern, and it should be
	// retained.
	}
	}

	private boolean createFormattingTemplate(NumberFormat format) {
	String numberFormat = format.getFormat();
	String numberPattern = format.getPattern();

	// The formatter doesn't format numbers when numberPattern contains "\|", e.g.
	// (20\|3)\d{4}. In those cases we quickly return.
	if (numberPattern.indexOf('\|') != -1) {
	return false;
	}

	// Replace anything in the form of [..] with \d
	numberPattern = CHARACTER_CLASS_PATTERN.matcher(numberPattern).replaceAll("\\\\d");

	// Replace any standalone digit (not the one in d{}) with \d
	numberPattern = STANDALONE_DIGIT_PATTERN.matcher(numberPattern).replaceAll("\\\\d");
	formattingTemplate.setLength(0);
	formattingTemplate.append(getFormattingTemplate(numberPattern, numberFormat));
	return true;
	}

	// Gets a formatting template which could be used to efficiently format a partial number where
	// digits are added one by one.
	private String getFormattingTemplate(String numberPattern, String numberFormat) {
	// Creates a phone number consisting only of the digit 9 that matches the
	// numberPattern by applying the pattern to the longestPhoneNumber string.
	String longestPhoneNumber = "999999999999999";
	Matcher m = regexCache.getPatternForRegex(numberPattern).matcher(longestPhoneNumber);
	m.find(); // this will always succeed
	String aPhoneNumber = m.group();
	// Formats the number according to numberFormat
	String template = aPhoneNumber.replaceAll(numberPattern, numberFormat);
	// Replaces each digit with character digitPlaceholder
	template = template.replaceAll("9", digitPlaceholder);
	return template;
	}

	/**
	* Clears the internal state of the formatter, so it could be reused.
	*/
	public void clear() {
	currentOutput = "";
	accruedInput.setLength(0);
	accruedInputWithoutFormatting.setLength(0);
	formattingTemplate.setLength(0);
	lastMatchPosition = 0;
	currentFormattingPattern = "";
	prefixBeforeNationalNumber.setLength(0);
	nationalNumber.setLength(0);
	ableToFormat = true;
	positionToRemember = 0;
	originalPosition = 0;
	isInternationalFormatting = false;
	isExpectingCountryCode = false;
	possibleFormats.clear();
	if (!currentMetaData.equals(defaultMetaData)) {
	initializeCountrySpecificInfo(defaultCountry);
	}
	}

	/**
	* Formats a phone number on-the-fly as each digit is entered.
	*
	* @param nextChar the most recently entered digit of a phone number. Formatting characters are
	* allowed, but they are removed from the result. Full width digits and Arabic-indic digits
	* are allowed, and will be shown as they are.
	* @return the partially formatted phone number.
	*/
	public String inputDigit(char nextChar) {
	currentOutput = inputDigitWithOptionToRememberPosition(nextChar, false);
	return currentOutput;
	}

	/**
	* Same as inputDigit, but remembers the position where nextChar is inserted, so that it could be
	* retrieved later by using getRememberedPosition(). The remembered position will be automatically
	* adjusted if additional formatting characters are later inserted/removed in front of nextChar.
	*/
	public String inputDigitAndRememberPosition(char nextChar) {
	currentOutput = inputDigitWithOptionToRememberPosition(nextChar, true);
	return currentOutput;
	}

	@SuppressWarnings(value = "fallthrough")
	private String inputDigitWithOptionToRememberPosition(char nextChar, boolean rememberPosition) {
	accruedInput.append(nextChar);
	if (rememberPosition) {
	originalPosition = accruedInput.length();
	}
	// We do formatting on-the-fly only when each character entered is either a plus sign or a
	// digit.
	if (!PhoneNumberUtil.VALID_START_CHAR_PATTERN.matcher(Character.toString(nextChar)).matches()) {
	ableToFormat = false;
	}
	if (!ableToFormat) {
	return accruedInput.toString();
	}

	nextChar = normalizeAndAccrueDigitsAndPlusSign(nextChar, rememberPosition);

	// We start to attempt to format only when at least MIN_LEADING_DIGITS_LENGTH digits (the plus
	// sign is counted as a digit as well for this purpose) have been entered.
	switch (accruedInputWithoutFormatting.length()) {
	case 0: // this is the case where the first few inputs are neither digits nor the plus sign.
	case 1:
	case 2:
	return accruedInput.toString();
	case 3:
	if (attemptToExtractIdd()) {
	isExpectingCountryCode = true;
	} else { // No IDD or plus sign is found, must be entering in national format.
	removeNationalPrefixFromNationalNumber();
	return attemptToChooseFormattingPattern();
	}
	case 4:
	case 5:
	if (isExpectingCountryCode) {
	if (attemptToExtractCountryCode()) {
	isExpectingCountryCode = false;
	}
	return prefixBeforeNationalNumber + nationalNumber.toString();
	}
	// We make a last attempt to extract a country code at the 6th digit because the maximum
	// length of IDD and country code are both 3.
	case 6:
	if (isExpectingCountryCode && !attemptToExtractCountryCode()) {
	ableToFormat = false;
	return accruedInput.toString();
	}
	default:
	if (possibleFormats.size() > 0) { // The formatting pattern is already chosen.
	String tempNationalNumber = inputDigitHelper(nextChar);
	// See if the accrued digits can be formatted properly already. If not, use the results
	// from inputDigitHelper, which does formatting based on the formatting pattern chosen.
	String formattedNumber = attemptToFormatAccruedDigits();
	if (formattedNumber.length() > 0) {
	return formattedNumber;
	}
	narrowDownPossibleFormats(nationalNumber.toString());
	if (maybeCreateNewTemplate()) {
	return inputAccruedNationalNumber();
	}
	return ableToFormat
	? prefixBeforeNationalNumber + tempNationalNumber
	: tempNationalNumber;
	} else {
	return attemptToChooseFormattingPattern();
	}
	}
	}

	String attemptToFormatAccruedDigits() {
	for (NumberFormat numFormat : possibleFormats) {
	Matcher m = regexCache.getPatternForRegex(numFormat.getPattern()).matcher(nationalNumber);
	if (m.matches()) {
	String formattedNumber = m.replaceAll(numFormat.getFormat());
	return prefixBeforeNationalNumber + formattedNumber;
	}
	}
	return "";
	}

	/**
	* Returns the current position in the partially formatted phone number of the character which was
	* previously passed in as the parameter of inputDigitAndRememberPosition().
	*/
	public int getRememberedPosition() {
	if (!ableToFormat) {
	return originalPosition;
	}
	int accruedInputIndex = 0, currentOutputIndex = 0;
	while (accruedInputIndex < positionToRemember) {
	if (accruedInputWithoutFormatting.charAt(accruedInputIndex) ==
	currentOutput.charAt(currentOutputIndex)) {
	accruedInputIndex++;
	currentOutputIndex++;
	} else {
	currentOutputIndex++;
	}
	}
	return currentOutputIndex;
	}

	// Attempts to set the formatting template and returns a string which contains the formatted
	// version of the digits entered so far.
	private String attemptToChooseFormattingPattern() {
	// We start to attempt to format only when as least MIN_LEADING_DIGITS_LENGTH digits of national
	// number (excluding national prefix) have been entered.
	if (nationalNumber.length() >= MIN_LEADING_DIGITS_LENGTH) {
	getAvailableFormats(nationalNumber.substring(0, MIN_LEADING_DIGITS_LENGTH));
	maybeCreateNewTemplate();
	return inputAccruedNationalNumber();
	} else {
	return prefixBeforeNationalNumber + nationalNumber.toString();
	}
	}

	// Invokes inputDigitHelper on each digit of the national number accrued, and returns a formatted
	// string in the end.
	private String inputAccruedNationalNumber() {
	int lengthOfNationalNumber = nationalNumber.length();
	if (lengthOfNationalNumber > 0) {
	String tempNationalNumber = "";
	for (int i = 0; i < lengthOfNationalNumber; i++) {
	tempNationalNumber = inputDigitHelper(nationalNumber.charAt(i));
	}
	return ableToFormat
	? prefixBeforeNationalNumber + tempNationalNumber
	: tempNationalNumber;
	} else {
	return prefixBeforeNationalNumber.toString();
	}
	}

	private void removeNationalPrefixFromNationalNumber() {
	int startOfNationalNumber = 0;
	if (currentMetaData.getCountryCode() == 1 && nationalNumber.charAt(0) == '1') {
	startOfNationalNumber = 1;
	prefixBeforeNationalNumber.append("1 ");
	isInternationalFormatting = true;
	} else if (currentMetaData.hasNationalPrefix()) {
	Matcher m = nationalPrefixForParsing.matcher(nationalNumber);
	if (m.lookingAt()) {
	startOfNationalNumber = m.end();
	prefixBeforeNationalNumber.append(nationalNumber.substring(0, startOfNationalNumber));
	}
	}
	nationalNumber.delete(0, startOfNationalNumber);
	}

	/**
	* Extracts IDD and plus sign to prefixBeforeNationalNumber when they are available, and places
	* the remaining input into nationalNumber.
	*
	* @return true when accruedInputWithoutFormatting begins with the plus sign or valid IDD for
	* defaultCountry.
	*/
	private boolean attemptToExtractIdd() {
	Matcher iddMatcher = internationalPrefix.matcher(accruedInputWithoutFormatting);
	if (iddMatcher.lookingAt()) {
	isInternationalFormatting = true;
	int startOfCountryCode = iddMatcher.end();
	nationalNumber.setLength(0);
	nationalNumber.append(accruedInputWithoutFormatting.substring(startOfCountryCode));
	prefixBeforeNationalNumber.append(
	accruedInputWithoutFormatting.substring(0, startOfCountryCode));
	if (accruedInputWithoutFormatting.charAt(0) != PhoneNumberUtil.PLUS_SIGN) {
	prefixBeforeNationalNumber.append(" ");
	}
	return true;
	}
	return false;
	}

	/**
	* Extracts country code from the beginning of nationalNumber to prefixBeforeNationalNumber when
	* they are available, and places the remaining input into nationalNumber.
	*
	* @return true when a valid country code can be found.
	*/
	private boolean attemptToExtractCountryCode() {
	if (nationalNumber.length() == 0) {
	return false;
	}
	StringBuffer numberWithoutCountryCode = new StringBuffer();
	int countryCode = phoneUtil.extractCountryCode(nationalNumber, numberWithoutCountryCode);
	if (countryCode == 0) {
	return false;
	} else {
	nationalNumber.setLength(0);
	nationalNumber.append(numberWithoutCountryCode);
	String newRegionCode = phoneUtil.getRegionCodeForCountryCode(countryCode);
	if (!newRegionCode.equals(defaultCountry)) {
	initializeCountrySpecificInfo(newRegionCode);
	}
	String countryCodeString = Integer.toString(countryCode);
	prefixBeforeNationalNumber.append(countryCodeString).append(" ");
	}
	return true;
	}

	// Accrues digits and the plus sign to accruedInputWithoutFormatting for later use. If nextChar
	// contains a digit in non-ASCII format (e.g. the full-width version of digits), it is first
	// normalized to the ASCII version. The return value is nextChar itself, or its normalized
	// version, if nextChar is a digit in non-ASCII format.
	private char normalizeAndAccrueDigitsAndPlusSign(char nextChar, boolean rememberPosition) {
	if (nextChar == PhoneNumberUtil.PLUS_SIGN) {
	accruedInputWithoutFormatting.append(nextChar);
	}
	if (PhoneNumberUtil.DIGIT_MAPPINGS.containsKey(nextChar)) {
	nextChar = PhoneNumberUtil.DIGIT_MAPPINGS.get(nextChar);
	accruedInputWithoutFormatting.append(nextChar);
	nationalNumber.append(nextChar);
	}
	if (rememberPosition) {
	positionToRemember = accruedInputWithoutFormatting.length();
	}
	return nextChar;
	}

	private String inputDigitHelper(char nextChar) {
	Matcher digitMatcher = digitPattern.matcher(formattingTemplate);
	if (digitMatcher.find(lastMatchPosition)) {
	String tempTemplate = digitMatcher.replaceFirst(Character.toString(nextChar));
	formattingTemplate.replace(0, tempTemplate.length(), tempTemplate);
	lastMatchPosition = digitMatcher.start();
	return formattingTemplate.substring(0, lastMatchPosition + 1);
	} else { // More digits are entered than we could handle.
	ableToFormat = false;
	return accruedInput.toString();
	}
	}
	}