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/*
* Copyright (C) 2007 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.IntDef;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.app.ActivityThread;
import android.compat.annotation.UnsupportedAppUsage;
import android.content.Context;
import android.os.Build;
import android.telephony.PhoneNumberUtils;
import android.telephony.TelephonyManager;
import android.text.Spannable;
import android.text.SpannableString;
import android.text.Spanned;
import android.text.method.LinkMovementMethod;
import android.text.method.MovementMethod;
import android.text.style.URLSpan;
import android.util.Log;
import android.util.Patterns;
import android.webkit.WebView;
import android.widget.TextView;
import com.android.i18n.phonenumbers.PhoneNumberMatch;
import com.android.i18n.phonenumbers.PhoneNumberUtil;
import com.android.i18n.phonenumbers.PhoneNumberUtil.Leniency;
import libcore.util.EmptyArray;
import java.io.UnsupportedEncodingException;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Locale;
import java.util.function.Function;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* Linkify take a piece of text and a regular expression and turns all of the
* regex matches in the text into clickable links. This is particularly
* useful for matching things like email addresses, web URLs, etc. and making
* them actionable.
*
* Alone with the pattern that is to be matched, a URL scheme prefix is also
* required. Any pattern match that does not begin with the supplied scheme
* will have the scheme prepended to the matched text when the clickable URL
* is created. For instance, if you are matching web URLs you would supply
* the scheme http://. If the pattern matches example.com, which
* does not have a URL scheme prefix, the supplied scheme will be prepended to
* create http://example.com when the clickable URL link is
* created.
*
* Note: When using {@link #MAP_ADDRESSES} or {@link #ALL}
* to match street addresses on API level {@link android.os.Build.VERSION_CODES#O_MR1}
* and earlier, methods in this class may throw
* {@link android.util.AndroidRuntimeException} or other exceptions if the
* device's WebView implementation is currently being updated, because
* {@link android.webkit.WebView#findAddress} is required to match street
* addresses.
*
* @see MatchFilter
* @see TransformFilter
*/
public class Linkify {
private static final String LOG_TAG = "Linkify";
/**
* Bit field indicating that web URLs should be matched in methods that
* take an options mask
*/
public static final int WEB_URLS = 0x01;
/**
* Bit field indicating that email addresses should be matched in methods
* that take an options mask
*/
public static final int EMAIL_ADDRESSES = 0x02;
/**
* Bit field indicating that phone numbers should be matched in methods that
* take an options mask
*/
public static final int PHONE_NUMBERS = 0x04;
/**
* Bit field indicating that street addresses should be matched in methods that
* take an options mask. Note that this should be avoided, as it uses the
* {@link android.webkit.WebView#findAddress(String)} method, which has various
* limitations and has been deprecated: see the documentation for
* {@link android.webkit.WebView#findAddress(String)} for more information.
*
* @deprecated use {@link android.view.textclassifier.TextClassifier#generateLinks(
* TextLinks.Request)} instead, and avoid {@link #MAP_ADDRESSES} even when targeting API levels
* where no alternative is available.
*/
@Deprecated
public static final int MAP_ADDRESSES = 0x08;
/**
* Bit mask indicating that all available patterns should be matched in methods
* that take an options mask. Note that this should be avoided, as the {@link
* #MAP_ADDRESSES} field uses the {@link android.webkit.WebView#findAddress(
* String)} method, which has various limitations and has been deprecated: see
* the documentation for {@link android.webkit.WebView#findAddress(String)} for
* more information.
*
* @deprecated use {@link android.view.textclassifier.TextClassifier#generateLinks(
* TextLinks.Request)} instead, and avoid {@link #ALL} even when targeting API levels where no
* alternative is available.
*/
@Deprecated
public static final int ALL = WEB_URLS | EMAIL_ADDRESSES | PHONE_NUMBERS | MAP_ADDRESSES;
/**
* Don't treat anything with fewer than this many digits as a
* phone number.
*/
private static final int PHONE_NUMBER_MINIMUM_DIGITS = 5;
/** @hide */
@IntDef(flag = true, value = { WEB_URLS, EMAIL_ADDRESSES, PHONE_NUMBERS, MAP_ADDRESSES, ALL })
@Retention(RetentionPolicy.SOURCE)
public @interface LinkifyMask {}
/**
* Filters out web URL matches that occur after an at-sign (@). This is
* to prevent turning the domain name in an email address into a web link.
*/
public static final MatchFilter sUrlMatchFilter = new MatchFilter() {
public final boolean acceptMatch(CharSequence s, int start, int end) {
if (start == 0) {
return true;
}
if (s.charAt(start - 1) == '@') {
return false;
}
return true;
}
};
/**
* Filters out URL matches that don't have enough digits to be a
* phone number.
*/
public static final MatchFilter sPhoneNumberMatchFilter = new MatchFilter() {
public final boolean acceptMatch(CharSequence s, int start, int end) {
int digitCount = 0;
for (int i = start; i < end; i++) {
if (Character.isDigit(s.charAt(i))) {
digitCount++;
if (digitCount >= PHONE_NUMBER_MINIMUM_DIGITS) {
return true;
}
}
}
return false;
}
};
/**
* Transforms matched phone number text into something suitable
* to be used in a tel: URL. It does this by removing everything
* but the digits and plus signs. For instance:
* '+1 (919) 555-1212'
* becomes '+19195551212'
*/
public static final TransformFilter sPhoneNumberTransformFilter = new TransformFilter() {
public final String transformUrl(final Matcher match, String url) {
return Patterns.digitsAndPlusOnly(match);
}
};
/**
* MatchFilter enables client code to have more control over
* what is allowed to match and become a link, and what is not.
*
* For example: when matching web URLs you would like things like
* http://www.example.com to match, as well as just example.com itelf.
* However, you would not want to match against the domain in
* [email protected]. So, when matching against a web URL pattern you
* might also include a MatchFilter that disallows the match if it is
* immediately preceded by an at-sign (@).
*/
public interface MatchFilter {
/**
* Examines the character span matched by the pattern and determines
* if the match should be turned into an actionable link.
*
* @param s The body of text against which the pattern
* was matched
* @param start The index of the first character in s that was
* matched by the pattern - inclusive
* @param end The index of the last character in s that was
* matched - exclusive
*
* @return Whether this match should be turned into a link
*/
boolean acceptMatch(CharSequence s, int start, int end);
}
/**
* TransformFilter enables client code to have more control over
* how matched patterns are represented as URLs.
*
* For example: when converting a phone number such as (919) 555-1212
* into a tel: URL the parentheses, white space, and hyphen need to be
* removed to produce tel:9195551212.
*/
public interface TransformFilter {
/**
* Examines the matched text and either passes it through or uses the
* data in the Matcher state to produce a replacement.
*
* @param match The regex matcher state that found this URL text
* @param url The text that was matched
*
* @return The transformed form of the URL
*/
String transformUrl(final Matcher match, String url);
}
/**
* Scans the text of the provided Spannable and turns all occurrences
* of the link types indicated in the mask into clickable links.
* If the mask is nonzero, it also removes any existing URLSpans
* attached to the Spannable, to avoid problems if you call it
* repeatedly on the same text.
*
* @param text Spannable whose text is to be marked-up with links
* @param mask Mask to define which kinds of links will be searched.
*
* @return True if at least one link is found and applied.
*
* @see #addLinks(Spannable, int, Function)
*/
public static final boolean addLinks(@NonNull Spannable text, @LinkifyMask int mask) {
return addLinks(text, mask, null, null);
}
/**
* Scans the text of the provided Spannable and turns all occurrences
* of the link types indicated in the mask into clickable links.
* If the mask is nonzero, it also removes any existing URLSpans
* attached to the Spannable, to avoid problems if you call it
* repeatedly on the same text.
*
* @param text Spannable whose text is to be marked-up with links
* @param mask mask to define which kinds of links will be searched
* @param urlSpanFactory function used to create {@link URLSpan}s
* @return True if at least one link is found and applied.
*/
public static final boolean addLinks(@NonNull Spannable text, @LinkifyMask int mask,
@Nullable Function urlSpanFactory) {
return addLinks(text, mask, null, urlSpanFactory);
}
/**
* Scans the text of the provided Spannable and turns all occurrences of the link types
* indicated in the mask into clickable links. If the mask is nonzero, it also removes any
* existing URLSpans attached to the Spannable, to avoid problems if you call it repeatedly
* on the same text.
*
* @param text Spannable whose text is to be marked-up with links
* @param mask mask to define which kinds of links will be searched
* @param context Context to be used while identifying phone numbers
* @param urlSpanFactory function used to create {@link URLSpan}s
* @return true if at least one link is found and applied.
*/
private static boolean addLinks(@NonNull Spannable text, @LinkifyMask int mask,
@Nullable Context context, @Nullable Function urlSpanFactory) {
if (text != null && containsUnsupportedCharacters(text.toString())) {
android.util.EventLog.writeEvent(0x534e4554, "116321860", -1, "");
return false;
}
if (mask == 0) {
return false;
}
final URLSpan[] old = text.getSpans(0, text.length(), URLSpan.class);
for (int i = old.length - 1; i >= 0; i--) {
text.removeSpan(old[i]);
}
final ArrayList links = new ArrayList();
if ((mask & WEB_URLS) != 0) {
gatherLinks(links, text, Patterns.AUTOLINK_WEB_URL,
new String[] { "http://", "https://", "rtsp://", "ftp://" },
sUrlMatchFilter, null);
}
if ((mask & EMAIL_ADDRESSES) != 0) {
gatherLinks(links, text, Patterns.AUTOLINK_EMAIL_ADDRESS,
new String[] { "mailto:" },
null, null);
}
if ((mask & PHONE_NUMBERS) != 0) {
gatherTelLinks(links, text, context);
}
if ((mask & MAP_ADDRESSES) != 0) {
gatherMapLinks(links, text);
}
pruneOverlaps(links);
if (links.size() == 0) {
return false;
}
for (LinkSpec link: links) {
applyLink(link.url, link.start, link.end, text, urlSpanFactory);
}
return true;
}
/**
* Returns true if the specified text contains at least one unsupported character for applying
* links. Also logs the error.
*
* @param text the text to apply links to
* @hide
*/
public static boolean containsUnsupportedCharacters(String text) {
if (text.contains("\u202C")) {
Log.e(LOG_TAG, "Unsupported character for applying links: u202C");
return true;
}
if (text.contains("\u202D")) {
Log.e(LOG_TAG, "Unsupported character for applying links: u202D");
return true;
}
if (text.contains("\u202E")) {
Log.e(LOG_TAG, "Unsupported character for applying links: u202E");
return true;
}
return false;
}
/**
* Scans the text of the provided TextView and turns all occurrences of
* the link types indicated in the mask into clickable links. If matches
* are found the movement method for the TextView is set to
* LinkMovementMethod.
*
* @param text TextView whose text is to be marked-up with links
* @param mask Mask to define which kinds of links will be searched.
*
* @return True if at least one link is found and applied.
*
* @see #addLinks(Spannable, int, Function)
*/
public static final boolean addLinks(@NonNull TextView text, @LinkifyMask int mask) {
if (mask == 0) {
return false;
}
final Context context = text.getContext();
final CharSequence t = text.getText();
if (t instanceof Spannable) {
if (addLinks((Spannable) t, mask, context, null)) {
addLinkMovementMethod(text);
return true;
}
return false;
} else {
SpannableString s = SpannableString.valueOf(t);
if (addLinks(s, mask, context, null)) {
addLinkMovementMethod(text);
text.setText(s);
return true;
}
return false;
}
}
private static final void addLinkMovementMethod(@NonNull TextView t) {
MovementMethod m = t.getMovementMethod();
if ((m == null) || !(m instanceof LinkMovementMethod)) {
if (t.getLinksClickable()) {
t.setMovementMethod(LinkMovementMethod.getInstance());
}
}
}
/**
* Applies a regex to the text of a TextView turning the matches into
* links. If links are found then UrlSpans are applied to the link
* text match areas, and the movement method for the text is changed
* to LinkMovementMethod.
*
* @param text TextView whose text is to be marked-up with links
* @param pattern Regex pattern to be used for finding links
* @param scheme URL scheme string (eg http://) to be
* prepended to the links that do not start with this scheme.
*/
public static final void addLinks(@NonNull TextView text, @NonNull Pattern pattern,
@Nullable String scheme) {
addLinks(text, pattern, scheme, null, null, null);
}
/**
* Applies a regex to the text of a TextView turning the matches into
* links. If links are found then UrlSpans are applied to the link
* text match areas, and the movement method for the text is changed
* to LinkMovementMethod.
*
* @param text TextView whose text is to be marked-up with links
* @param pattern Regex pattern to be used for finding links
* @param scheme URL scheme string (eg http://) to be
* prepended to the links that do not start with this scheme.
* @param matchFilter The filter that is used to allow the client code
* additional control over which pattern matches are
* to be converted into links.
*/
public static final void addLinks(@NonNull TextView text, @NonNull Pattern pattern,
@Nullable String scheme, @Nullable MatchFilter matchFilter,
@Nullable TransformFilter transformFilter) {
addLinks(text, pattern, scheme, null, matchFilter, transformFilter);
}
/**
* Applies a regex to the text of a TextView turning the matches into
* links. If links are found then UrlSpans are applied to the link
* text match areas, and the movement method for the text is changed
* to LinkMovementMethod.
*
* @param text TextView whose text is to be marked-up with links.
* @param pattern Regex pattern to be used for finding links.
* @param defaultScheme The default scheme to be prepended to links if the link does not
* start with one of the schemes given.
* @param schemes Array of schemes (eg http://) to check if the link found
* contains a scheme. Passing a null or empty value means prepend defaultScheme
* to all links.
* @param matchFilter The filter that is used to allow the client code additional control
* over which pattern matches are to be converted into links.
* @param transformFilter Filter to allow the client code to update the link found.
*/
public static final void addLinks(@NonNull TextView text, @NonNull Pattern pattern,
@Nullable String defaultScheme, @Nullable String[] schemes,
@Nullable MatchFilter matchFilter, @Nullable TransformFilter transformFilter) {
SpannableString spannable = SpannableString.valueOf(text.getText());
boolean linksAdded = addLinks(spannable, pattern, defaultScheme, schemes, matchFilter,
transformFilter);
if (linksAdded) {
text.setText(spannable);
addLinkMovementMethod(text);
}
}
/**
* Applies a regex to a Spannable turning the matches into
* links.
*
* @param text Spannable whose text is to be marked-up with links
* @param pattern Regex pattern to be used for finding links
* @param scheme URL scheme string (eg http://) to be
* prepended to the links that do not start with this scheme.
* @see #addLinks(Spannable, Pattern, String, String[], MatchFilter, TransformFilter, Function)
*/
public static final boolean addLinks(@NonNull Spannable text, @NonNull Pattern pattern,
@Nullable String scheme) {
return addLinks(text, pattern, scheme, null, null, null);
}
/**
* Applies a regex to a Spannable turning the matches into
* links.
*
* @param spannable Spannable whose text is to be marked-up with links
* @param pattern Regex pattern to be used for finding links
* @param scheme URL scheme string (eg http://) to be
* prepended to the links that do not start with this scheme.
* @param matchFilter The filter that is used to allow the client code
* additional control over which pattern matches are
* to be converted into links.
* @param transformFilter Filter to allow the client code to update the link found.
*
* @return True if at least one link is found and applied.
* @see #addLinks(Spannable, Pattern, String, String[], MatchFilter, TransformFilter, Function)
*/
public static final boolean addLinks(@NonNull Spannable spannable, @NonNull Pattern pattern,
@Nullable String scheme, @Nullable MatchFilter matchFilter,
@Nullable TransformFilter transformFilter) {
return addLinks(spannable, pattern, scheme, null, matchFilter,
transformFilter);
}
/**
* Applies a regex to a Spannable turning the matches into links.
*
* @param spannable Spannable whose text is to be marked-up with links.
* @param pattern Regex pattern to be used for finding links.
* @param defaultScheme The default scheme to be prepended to links if the link does not
* start with one of the schemes given.
* @param schemes Array of schemes (eg http://) to check if the link found
* contains a scheme. Passing a null or empty value means prepend defaultScheme
* to all links.
* @param matchFilter The filter that is used to allow the client code additional control
* over which pattern matches are to be converted into links.
* @param transformFilter Filter to allow the client code to update the link found.
*
* @return True if at least one link is found and applied.
*
* @see #addLinks(Spannable, Pattern, String, String[], MatchFilter, TransformFilter, Function)
*/
public static final boolean addLinks(@NonNull Spannable spannable, @NonNull Pattern pattern,
@Nullable String defaultScheme, @Nullable String[] schemes,
@Nullable MatchFilter matchFilter, @Nullable TransformFilter transformFilter) {
return addLinks(spannable, pattern, defaultScheme, schemes, matchFilter, transformFilter,
null);
}
/**
* Applies a regex to a Spannable turning the matches into links.
*
* @param spannable spannable whose text is to be marked-up with links.
* @param pattern regex pattern to be used for finding links.
* @param defaultScheme the default scheme to be prepended to links if the link does not
* start with one of the schemes given.
* @param schemes array of schemes (eg http://) to check if the link found
* contains a scheme. Passing a null or empty value means prepend
* defaultScheme
* to all links.
* @param matchFilter the filter that is used to allow the client code additional control
* over which pattern matches are to be converted into links.
* @param transformFilter filter to allow the client code to update the link found.
* @param urlSpanFactory function used to create {@link URLSpan}s
*
* @return True if at least one link is found and applied.
*/
public static final boolean addLinks(@NonNull Spannable spannable, @NonNull Pattern pattern,
@Nullable String defaultScheme, @Nullable String[] schemes,
@Nullable MatchFilter matchFilter, @Nullable TransformFilter transformFilter,
@Nullable Function urlSpanFactory) {
if (spannable != null && containsUnsupportedCharacters(spannable.toString())) {
android.util.EventLog.writeEvent(0x534e4554, "116321860", -1, "");
return false;
}
final String[] schemesCopy;
if (defaultScheme == null) defaultScheme = "";
if (schemes == null || schemes.length < 1) {
schemes = EmptyArray.STRING;
}
schemesCopy = new String[schemes.length + 1];
schemesCopy[0] = defaultScheme.toLowerCase(Locale.ROOT);
for (int index = 0; index < schemes.length; index++) {
String scheme = schemes[index];
schemesCopy[index + 1] = (scheme == null) ? "" : scheme.toLowerCase(Locale.ROOT);
}
boolean hasMatches = false;
Matcher m = pattern.matcher(spannable);
while (m.find()) {
int start = m.start();
int end = m.end();
boolean allowed = true;
if (matchFilter != null) {
allowed = matchFilter.acceptMatch(spannable, start, end);
}
if (allowed) {
String url = makeUrl(m.group(0), schemesCopy, m, transformFilter);
applyLink(url, start, end, spannable, urlSpanFactory);
hasMatches = true;
}
}
return hasMatches;
}
private static void applyLink(String url, int start, int end, Spannable text,
@Nullable Function urlSpanFactory) {
if (urlSpanFactory == null) {
urlSpanFactory = DEFAULT_SPAN_FACTORY;
}
final URLSpan span = urlSpanFactory.apply(url);
text.setSpan(span, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
}
private static final String makeUrl(@NonNull String url, @NonNull String[] prefixes,
Matcher matcher, @Nullable TransformFilter filter) {
if (filter != null) {
url = filter.transformUrl(matcher, url);
}
boolean hasPrefix = false;
for (int i = 0; i < prefixes.length; i++) {
if (url.regionMatches(true, 0, prefixes[i], 0, prefixes[i].length())) {
hasPrefix = true;
// Fix capitalization if necessary
if (!url.regionMatches(false, 0, prefixes[i], 0, prefixes[i].length())) {
url = prefixes[i] + url.substring(prefixes[i].length());
}
break;
}
}
if (!hasPrefix && prefixes.length > 0) {
url = prefixes[0] + url;
}
return url;
}
private static final void gatherLinks(ArrayList links,
Spannable s, Pattern pattern, String[] schemes,
MatchFilter matchFilter, TransformFilter transformFilter) {
Matcher m = pattern.matcher(s);
while (m.find()) {
int start = m.start();
int end = m.end();
if (matchFilter == null || matchFilter.acceptMatch(s, start, end)) {
LinkSpec spec = new LinkSpec();
String url = makeUrl(m.group(0), schemes, m, transformFilter);
spec.url = url;
spec.start = start;
spec.end = end;
links.add(spec);
}
}
}
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
private static void gatherTelLinks(ArrayList links, Spannable s,
@Nullable Context context) {
PhoneNumberUtil phoneUtil = PhoneNumberUtil.getInstance();
final Context ctx = (context != null) ? context : ActivityThread.currentApplication();
final String regionCode = (ctx != null) ? ctx.getSystemService(TelephonyManager.class).
getSimCountryIso().toUpperCase(Locale.US) : Locale.getDefault().getCountry();
Iterable matches = phoneUtil.findNumbers(s.toString(),
regionCode, Leniency.POSSIBLE, Long.MAX_VALUE);
for (PhoneNumberMatch match : matches) {
LinkSpec spec = new LinkSpec();
spec.url = "tel:" + PhoneNumberUtils.normalizeNumber(match.rawString());
spec.start = match.start();
spec.end = match.end();
links.add(spec);
}
}
private static final void gatherMapLinks(ArrayList links, Spannable s) {
String string = s.toString();
String address;
int base = 0;
try {
while ((address = WebView.findAddress(string)) != null) {
int start = string.indexOf(address);
if (start < 0) {
break;
}
LinkSpec spec = new LinkSpec();
int length = address.length();
int end = start + length;
spec.start = base + start;
spec.end = base + end;
string = string.substring(end);
base += end;
String encodedAddress = null;
try {
encodedAddress = URLEncoder.encode(address,"UTF-8");
} catch (UnsupportedEncodingException e) {
continue;
}
spec.url = "geo:0,0?q=" + encodedAddress;
links.add(spec);
}
} catch (UnsupportedOperationException e) {
// findAddress may fail with an unsupported exception on platforms without a WebView.
// In this case, we will not append anything to the links variable: it would have died
// in WebView.findAddress.
return;
}
}
private static final void pruneOverlaps(ArrayList links) {
Comparator c = new Comparator() {
public final int compare(LinkSpec a, LinkSpec b) {
if (a.start < b.start) {
return -1;
}
if (a.start > b.start) {
return 1;
}
if (a.end < b.end) {
return 1;
}
if (a.end > b.end) {
return -1;
}
return 0;
}
};
Collections.sort(links, c);
int len = links.size();
int i = 0;
while (i < len - 1) {
LinkSpec a = links.get(i);
LinkSpec b = links.get(i + 1);
int remove = -1;
if ((a.start <= b.start) && (a.end > b.start)) {
if (b.end <= a.end) {
remove = i + 1;
} else if ((a.end - a.start) > (b.end - b.start)) {
remove = i + 1;
} else if ((a.end - a.start) < (b.end - b.start)) {
remove = i;
}
if (remove != -1) {
links.remove(remove);
len--;
continue;
}
}
i++;
}
}
/**
* Default factory function to create {@link URLSpan}s. While adding spans to a
* {@link Spannable}, {@link Linkify} will call this function to create a {@link URLSpan}.
*/
private static final Function DEFAULT_SPAN_FACTORY =
(String string) -> new URLSpan(string);
}
class LinkSpec {
String url;
int start;
int end;
}