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8276660: Scalability bottleneck in java.security.Provider.getService()

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Reviewed-by: weijun
This commit is contained in:
Valerie Peng 2021-12-08 17:44:10 +00:00
parent 2478158815
commit 9b747491de
1 changed files with 276 additions and 227 deletions
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503
src/java.base/share/classes/java/security/Provider.java
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@ -191,6 +191,8 @@ public abstract class Provider extends Properties {
this.versionStr = Double.toString(version);
this.info = info;
this.serviceMap = new ConcurrentHashMap<>();
this.legacyMap = new ConcurrentHashMap<>();
this.prngAlgos = new LinkedHashSet<String>(6);
putId();
initialized = true;
}
@ -229,6 +231,8 @@ public abstract class Provider extends Properties {
this.version = parseVersionStr(versionStr);
this.info = info;
this.serviceMap = new ConcurrentHashMap<>();
this.legacyMap = new ConcurrentHashMap<>();
this.prngAlgos = new LinkedHashSet<String>(6);
putId();
initialized = true;
}
@ -572,7 +576,6 @@ public abstract class Provider extends Properties {
public synchronized boolean replace(Object key, Object oldValue,
Object newValue) {
check("putProviderProperty." + name);
if (debug != null) {
debug.println("Replace " + name + " provider property " + key);
}
@ -598,7 +601,6 @@ public abstract class Provider extends Properties {
@Override
public synchronized Object replace(Object key, Object value) {
check("putProviderProperty." + name);
if (debug != null) {
debug.println("Replace " + name + " provider property " + key);
}
@ -627,7 +629,6 @@ public abstract class Provider extends Properties {
public synchronized void replaceAll(BiFunction<? super Object,
? super Object, ? extends Object> function) {
check("putProviderProperty." + name);
if (debug != null) {
debug.println("ReplaceAll " + name + " provider property ");
}
@ -657,7 +658,6 @@ public abstract class Provider extends Properties {
? super Object, ? extends Object> remappingFunction) {
check("putProviderProperty." + name);
check("removeProviderProperty." + name);
if (debug != null) {
debug.println("Compute " + name + " provider property " + key);
}
@ -684,11 +684,10 @@ public abstract class Provider extends Properties {
* @since 1.8
*/
@Override
public synchronized Object computeIfAbsent(Object key, Function<? super Object,
? extends Object> mappingFunction) {
public synchronized Object computeIfAbsent(Object key,
Function<? super Object, ? extends Object> mappingFunction) {
check("putProviderProperty." + name);
check("removeProviderProperty." + name);
if (debug != null) {
debug.println("ComputeIfAbsent " + name + " provider property " +
key);
@ -714,11 +713,11 @@ public abstract class Provider extends Properties {
* @since 1.8
*/
@Override
public synchronized Object computeIfPresent(Object key, BiFunction<? super Object,
? super Object, ? extends Object> remappingFunction) {
public synchronized Object computeIfPresent(Object key,
BiFunction<? super Object, ? super Object, ? extends Object>
remappingFunction) {
check("putProviderProperty." + name);
check("removeProviderProperty." + name);
if (debug != null) {
debug.println("ComputeIfPresent " + name + " provider property " +
key);
@ -747,11 +746,11 @@ public abstract class Provider extends Properties {
* @since 1.8
*/
@Override
public synchronized Object merge(Object key, Object value, BiFunction<? super Object,
? super Object, ? extends Object> remappingFunction) {
public synchronized Object merge(Object key, Object value,
BiFunction<? super Object, ? super Object, ? extends Object>
remappingFunction) {
check("putProviderProperty." + name);
check("removeProviderProperty." + name);
if (debug != null) {
debug.println("Merge " + name + " provider property " + key);
}
@ -777,7 +776,8 @@ public abstract class Provider extends Properties {
* @since 1.8
*/
@Override
public synchronized void forEach(BiConsumer<? super Object, ? super Object> action) {
public synchronized void forEach(BiConsumer<? super Object, ? super Object>
action) {
checkInitialized();
super.forEach(action);
}
@ -817,14 +817,11 @@ public abstract class Provider extends Properties {
}
}
// legacy properties changed since last call to any services method?
private transient boolean legacyChanged;
// legacyMap changed since last call to getServices()
private transient volatile boolean legacyChanged;
// serviceMap changed since last call to getServices()
private transient volatile boolean servicesChanged;
// Map<String,String> used to keep track of legacy registration
private transient Map<String,String> legacyStrings;
// Map<ServiceKey,Service>
// used for services added via putService(), initialized on demand
private transient Map<ServiceKey,Service> serviceMap;
@ -832,6 +829,9 @@ public abstract class Provider extends Properties {
// For backward compatibility, the registration ordering of
// SecureRandom (RNG) algorithms needs to be preserved for
// "new SecureRandom()" calls when this provider is used
// NOTE: may need extra mechanism for providers to indicate their
// preferred ordering of SecureRandom algorithms since registration
// ordering info is lost once serialized
private transient Set<String> prngAlgos;
// Map<ServiceKey,Service>
@ -840,7 +840,7 @@ public abstract class Provider extends Properties {
// Set<Service>
// Unmodifiable set of all services. Initialized on demand.
private transient Set<Service> serviceSet;
private transient volatile Set<Service> serviceSet;
// register the id attributes for this provider
// this is to ensure that equals() and hashCode() do not incorrectly
@ -872,6 +872,7 @@ public abstract class Provider extends Properties {
for (Map.Entry<Object,Object> entry : super.entrySet()) {
copy.put(entry.getKey(), entry.getValue());
}
defaults = null;
in.defaultReadObject();
if (this.versionStr == null) {
@ -882,23 +883,22 @@ public abstract class Provider extends Properties {
this.version = parseVersionStr(this.versionStr);
}
this.serviceMap = new ConcurrentHashMap<>();
this.legacyMap = new ConcurrentHashMap<>();
this.prngAlgos = new LinkedHashSet<String>(6);
implClear();
initialized = true;
putAll(copy);
}
// check whether to update 'legacyString' with the specified key
private boolean checkLegacy(Object key) {
String keyString = (String)key;
if (keyString.startsWith("Provider.")) {
// returns false if no update necessary, i.e. key isn't String or
// is String but it's provider-related (name/version/info/className)
private static boolean checkLegacy(Object key) {
if (key instanceof String && ((String)key).startsWith("Provider.")) {
// ignore provider related updates
return false;
} else {
return true;
}
legacyChanged = true;
if (legacyStrings == null) {
legacyStrings = new LinkedHashMap<>();
}
return true;
}
/**
@ -913,149 +913,161 @@ public abstract class Provider extends Properties {
}
private Object implRemove(Object key) {
if (key instanceof String) {
if (!checkLegacy(key)) {
return null;
}
legacyStrings.remove((String)key);
if (!checkLegacy(key)) return null;
Object o = super.remove(key);
if (o instanceof String so && key instanceof String sk) {
parseLegacy(sk, so, OPType.REMOVE);
}
return super.remove(key);
return o;
}
private boolean implRemove(Object key, Object value) {
if (key instanceof String && value instanceof String) {
if (!checkLegacy(key)) {
return false;
}
legacyStrings.remove((String)key, (String)value);
if (!checkLegacy(key)) return false;
boolean result = super.remove(key, value);
if (result && key instanceof String sk && value instanceof String sv) {
parseLegacy(sk, sv, OPType.REMOVE);
}
return super.remove(key, value);
return result;
}
private boolean implReplace(Object key, Object oldValue, Object newValue) {
if ((key instanceof String) && (oldValue instanceof String) &&
(newValue instanceof String)) {
if (!checkLegacy(key)) {
return false;
if (!checkLegacy(key)) return false;
boolean result = super.replace(key, oldValue, newValue);
if (result && key instanceof String sk) {
if (newValue instanceof String sv) {
parseLegacy(sk, sv, OPType.ADD);
} else if (oldValue instanceof String sv) {
parseLegacy(sk, sv, OPType.REMOVE);
}
legacyStrings.replace((String)key, (String)oldValue,
(String)newValue);
}
return super.replace(key, oldValue, newValue);
return result;
}
private Object implReplace(Object key, Object value) {
if ((key instanceof String) && (value instanceof String)) {
if (!checkLegacy(key)) {
return null;
if (!checkLegacy(key)) return null;
Object o = super.replace(key, value);
if (key instanceof String sk) {
if (o instanceof String so) {
if (value instanceof String sv) {
parseLegacy(sk, sv, OPType.ADD);
} else {
parseLegacy(sk, so, OPType.REMOVE);
}
}
legacyStrings.replace((String)key, (String)value);
}
return super.replace(key, value);
return o;
}
@SuppressWarnings("unchecked") // Function must actually operate over strings
private void implReplaceAll(BiFunction<? super Object, ? super Object,
? extends Object> function) {
legacyChanged = true;
if (legacyStrings == null) {
legacyStrings = new LinkedHashMap<>();
} else {
legacyStrings.replaceAll((BiFunction<? super String, ? super String,
? extends String>) function);
}
super.replaceAll(function);
// clear out all existing mappings and start fresh
legacyMap.clear();
legacyChanged = true;
for (Map.Entry<Object, Object> entry : super.entrySet()) {
Object key = entry.getKey();
Object value = entry.getValue();
if ((key instanceof String sk) && (value instanceof String sv)) {
if (!checkLegacy(sk)) {
continue;
}
parseLegacy(sk, sv, OPType.ADD);
}
}
}
@SuppressWarnings("unchecked") // Function must actually operate over strings
private Object implMerge(Object key, Object value,
BiFunction<? super Object, ? super Object, ? extends Object>
remappingFunction) {
if ((key instanceof String) && (value instanceof String)) {
if (!checkLegacy(key)) {
return null;
if (!checkLegacy(key)) return null;
Object o = super.merge(key, value, remappingFunction);
if (key instanceof String sk) {
if (o == null) {
parseLegacy(sk, null, OPType.REMOVE);
} else if (o instanceof String so) {
parseLegacy(sk, so, OPType.ADD);
}
legacyStrings.merge((String)key, (String)value,
(BiFunction<? super String, ? super String,
? extends String>) remappingFunction);
}
return super.merge(key, value, remappingFunction);
return o;
}
@SuppressWarnings("unchecked") // Function must actually operate over strings
private Object implCompute(Object key, BiFunction<? super Object,
? super Object, ? extends Object> remappingFunction) {
if (key instanceof String) {
if (!checkLegacy(key)) {
return null;
if (!checkLegacy(key)) return null;
Object o = super.compute(key, remappingFunction);
if (key instanceof String sk) {
if (o == null) {
parseLegacy(sk, null, OPType.REMOVE);
} else if (o instanceof String so) {
parseLegacy(sk, so, OPType.ADD);
}
legacyStrings.compute((String) key,
(BiFunction<? super String,? super String,
? extends String>) remappingFunction);
}
return super.compute(key, remappingFunction);
return o;
}
@SuppressWarnings("unchecked") // Function must actually operate over strings
private Object implComputeIfAbsent(Object key, Function<? super Object,
? extends Object> mappingFunction) {
if (key instanceof String) {
if (!checkLegacy(key)) {
return null;
}
legacyStrings.computeIfAbsent((String) key,
(Function<? super String, ? extends String>)
mappingFunction);
if (!checkLegacy(key)) return null;
Object o = super.computeIfAbsent(key, mappingFunction);
if (o instanceof String so && key instanceof String sk) {
parseLegacy(sk, so, OPType.ADD);
}
return super.computeIfAbsent(key, mappingFunction);
return o;
}
@SuppressWarnings("unchecked") // Function must actually operate over strings
private Object implComputeIfPresent(Object key, BiFunction<? super Object,
? super Object, ? extends Object> remappingFunction) {
if (key instanceof String) {
if (!checkLegacy(key)) {
return null;
}
legacyStrings.computeIfPresent((String) key,
(BiFunction<? super String, ? super String,
? extends String>) remappingFunction);
if (!checkLegacy(key)) return null;
Object o = super.computeIfPresent(key, remappingFunction);
if (o instanceof String so && key instanceof String sk) {
parseLegacy(sk, so, OPType.ADD);
}
return super.computeIfPresent(key, remappingFunction);
return o;
}
private Object implPut(Object key, Object value) {
if ((key instanceof String) && (value instanceof String)) {
if (!checkLegacy(key)) {
return null;
}
legacyStrings.put((String)key, (String)value);
if (!checkLegacy(key)) return null;
Object o = super.put(key, value);
if (key instanceof String sk && value instanceof String sv) {
parseLegacy(sk, sv, OPType.ADD);
}
return super.put(key, value);
return o;
}
private Object implPutIfAbsent(Object key, Object value) {
if ((key instanceof String) && (value instanceof String)) {
if (!checkLegacy(key)) {
return null;
}
legacyStrings.putIfAbsent((String)key, (String)value);
if (!checkLegacy(key)) return null;
Object o = super.putIfAbsent(key, value);
if (o == null && key instanceof String sk &&
value instanceof String sv) {
parseLegacy(sk, sv, OPType.ADD);
}
return super.putIfAbsent(key, value);
return o;
}
private void implClear() {
if (legacyStrings != null) {
legacyStrings.clear();
}
if (legacyMap != null) {
legacyMap.clear();
}
legacyMap.clear();
serviceMap.clear();
legacyChanged = false;
servicesChanged = false;
serviceSet = null;
prngAlgos = null;
prngAlgos.clear();
super.clear();
putId();
}
@ -1085,40 +1097,8 @@ public abstract class Provider extends Properties {
boolean matches(String type, String algorithm) {
return (this.type == type) && (this.originalAlgorithm == algorithm);
}
}
/**
* Ensure all the legacy String properties are fully parsed into
* service objects.
*/
private void ensureLegacyParsed() {
if (legacyChanged == false || (legacyStrings == null)) {
return;
}
serviceSet = null;
if (legacyMap == null) {
legacyMap = new ConcurrentHashMap<>();
} else {
legacyMap.clear();
}
for (Map.Entry<String,String> entry : legacyStrings.entrySet()) {
parseLegacyPut(entry.getKey(), entry.getValue());
}
removeInvalidServices(legacyMap);
legacyChanged = false;
}
/**
* Remove all invalid services from the Map. Invalid services can only
* occur if the legacy properties are inconsistent or incomplete.
*/
private void removeInvalidServices(Map<ServiceKey,Service> map) {
for (Iterator<Map.Entry<ServiceKey, Service>> t =
map.entrySet().iterator(); t.hasNext(); ) {
Service s = t.next().getValue();
if (s.isValid() == false) {
t.remove();
}
public String toString() {
return type + "." + algorithm;
}
}
@ -1136,71 +1116,136 @@ public abstract class Provider extends Properties {
return new String[] {type, alg};
}
// utility method for getting a String with service type and algorithm
private static String getKey(Service s) {
return s.getType() + "." + s.getAlgorithm();
}
private static final String ALIAS_PREFIX = "Alg.Alias.";
private static final String ALIAS_PREFIX_LOWER = "alg.alias.";
private static final int ALIAS_LENGTH = ALIAS_PREFIX.length();
private void parseLegacyPut(String name, String value) {
private static enum OPType {
ADD, REMOVE;
}
private void parseLegacy(String name, String value, OPType opType) {
// alias
if (name.toLowerCase(ENGLISH).startsWith(ALIAS_PREFIX_LOWER)) {
// e.g. put("Alg.Alias.MessageDigest.SHA", "SHA-1");
// aliasKey ~ MessageDigest.SHA
String stdAlg = value;
String aliasKey = name.substring(ALIAS_LENGTH);
String[] typeAndAlg = getTypeAndAlgorithm(aliasKey);
String aliasKeyStr = name.substring(ALIAS_LENGTH);
String[] typeAndAlg = getTypeAndAlgorithm(aliasKeyStr);
if (typeAndAlg == null) {
return;
}
legacyChanged = true;
Objects.requireNonNull(value, "alias value should map to an alg");
String type = getEngineName(typeAndAlg[0]);
String aliasAlg = typeAndAlg[1].intern();
ServiceKey key = new ServiceKey(type, stdAlg, true);
Service s = legacyMap.get(key);
if (s == null) {
s = new Service(this, type, stdAlg);
legacyMap.put(key, s);
ServiceKey stdKey = new ServiceKey(type, value, true);
Service stdService = legacyMap.get(stdKey);
ServiceKey aliasKey = new ServiceKey(type, aliasAlg, true);
switch (opType) {
case ADD:
// clean up old alias if present
Service prevAliasService = legacyMap.get(aliasAlg);
if (prevAliasService != null) {
prevAliasService.removeAlias(aliasAlg);
}
if (stdService == null) {
// add standard mapping in order to add alias
stdService = new Service(this, type, value);
legacyMap.put(stdKey, stdService);
}
stdService.addAlias(aliasAlg);
legacyMap.put(aliasKey, stdService);
break;
case REMOVE:
if (stdService != null) {
stdService.removeAlias(aliasAlg);
}
legacyMap.remove(aliasKey);
break;
default:
throw new AssertionError();
}
legacyMap.put(new ServiceKey(type, aliasAlg, true), s);
s.addAlias(aliasAlg);
} else {
String[] typeAndAlg = getTypeAndAlgorithm(name);
if (typeAndAlg == null) {
return;
}
legacyChanged = true;
int i = typeAndAlg[1].indexOf(' ');
// regular registration
if (i == -1) {
// e.g. put("MessageDigest.SHA-1", "sun.security.provider.SHA");
String type = getEngineName(typeAndAlg[0]);
String stdAlg = typeAndAlg[1].intern();
String className = value;
ServiceKey key = new ServiceKey(type, stdAlg, true);
Service s = legacyMap.get(key);
if (s == null) {
s = new Service(this, type, stdAlg);
legacyMap.put(key, s);
}
s.className = className;
if (type.equals("SecureRandom")) {
updateSecureRandomEntries(true, s.algorithm);
ServiceKey stdKey = new ServiceKey(type, stdAlg, true);
Service stdService = legacyMap.get(stdKey);
switch (opType) {
case ADD:
Objects.requireNonNull(value,
"className can't be null");
if (stdService == null) {
stdService = new Service(this, type, stdAlg);
legacyMap.put(stdKey, stdService);
}
stdService.className = value;
break;
case REMOVE:
// only remove if value also matches when non-null
if (stdService != null) {
if (value == null) {
legacyMap.remove(stdKey);
} else if (stdService.className.equals(value)) {
legacyMap.remove(stdKey, stdService);
}
// remove all corresponding alias mappings
for (String alias : stdService.getAliases()) {
legacyMap.remove(new ServiceKey(type, alias,
true), stdService);
}
}
break;
default:
throw new AssertionError();
}
checkAndUpdateSecureRandom(type, stdAlg,
(opType != OPType.REMOVE));
} else { // attribute
// e.g. put("MessageDigest.SHA-1 ImplementedIn", "Software");
String attributeValue = value;
String type = getEngineName(typeAndAlg[0]);
String attributeString = typeAndAlg[1];
String stdAlg = attributeString.substring(0, i).intern();
String attributeName = attributeString.substring(i + 1);
String attrString = typeAndAlg[1];
String stdAlg = attrString.substring(0, i).intern();
String attrName = attrString.substring(i + 1);
// kill additional spaces
while (attributeName.startsWith(" ")) {
attributeName = attributeName.substring(1);
while (attrName.startsWith(" ")) {
attrName = attrName.substring(1);
}
attributeName = attributeName.intern();
ServiceKey key = new ServiceKey(type, stdAlg, true);
Service s = legacyMap.get(key);
if (s == null) {
s = new Service(this, type, stdAlg);
legacyMap.put(key, s);
attrName = attrName.intern();
ServiceKey stdKey = new ServiceKey(type, stdAlg, true);
Service stdService = legacyMap.get(stdKey);
switch (opType) {
case ADD:
Objects.requireNonNull(value,
"attribute value should not be null");
if (stdService == null) {
stdService = new Service(this, type, stdAlg);
legacyMap.put(stdKey, stdService);
}
stdService.addAttribute(attrName, value);
break;
case REMOVE:
if (stdService != null) {
stdService.removeAttribute(attrName, value);
}
break;
default:
throw new AssertionError();
}
s.addAttribute(attributeName, attributeValue);
}
}
}
@ -1227,25 +1272,25 @@ public abstract class Provider extends Properties {
*/
public Service getService(String type, String algorithm) {
checkInitialized();
// avoid allocating a new ServiceKey object if possible
ServiceKey key = previousKey;
if (key.matches(type, algorithm) == false) {
key = new ServiceKey(type, algorithm, false);
previousKey = key;
}
if (!serviceMap.isEmpty()) {
Service s = serviceMap.get(key);
if (s != null) {
return s;
}
Service s = serviceMap.get(key);
if (s != null) {
return s;
}
synchronized (this) {
ensureLegacyParsed();
if (legacyMap != null && !legacyMap.isEmpty()) {
return legacyMap.get(key);
}
s = legacyMap.get(key);
if (s != null && !s.isValid()) {
legacyMap.remove(key, s);
} else {
return s;
}
return null;
}
@ -1267,22 +1312,19 @@ public abstract class Provider extends Properties {
*
* @since 1.5
*/
public synchronized Set<Service> getServices() {
public Set<Service> getServices() {
checkInitialized();
if (legacyChanged || servicesChanged) {
serviceSet = null;
}
if (serviceSet == null) {
ensureLegacyParsed();
if (serviceSet == null || legacyChanged || servicesChanged) {
Set<Service> set = new LinkedHashSet<>();
if (!serviceMap.isEmpty()) {
set.addAll(serviceMap.values());
}
if (legacyMap != null && !legacyMap.isEmpty()) {
if (!legacyMap.isEmpty()) {
set.addAll(legacyMap.values());
}
serviceSet = Collections.unmodifiableSet(set);
servicesChanged = false;
legacyChanged = false;
}
return serviceSet;
}
@ -1339,44 +1381,36 @@ public abstract class Provider extends Properties {
servicesChanged = true;
synchronized (this) {
putPropertyStrings(s);
if (type.equals("SecureRandom")) {
updateSecureRandomEntries(true, s.algorithm);
}
checkAndUpdateSecureRandom(type, algorithm, true);
}
}
// keep tracks of the registered secure random algos and store them in order
private void updateSecureRandomEntries(boolean doAdd, String s) {
Objects.requireNonNull(s);
if (doAdd) {
if (prngAlgos == null) {
prngAlgos = new LinkedHashSet<String>();
private void checkAndUpdateSecureRandom(String type, String algo,
boolean doAdd) {
if (type.equalsIgnoreCase("SecureRandom")) {
if (doAdd) {
prngAlgos.add(algo);
} else {
prngAlgos.remove(algo);
}
if (debug != null) {
debug.println((doAdd? "Add":"Remove") +
" SecureRandom algo " + algo);
}
prngAlgos.add(s);
} else {
prngAlgos.remove(s);
}
if (debug != null) {
debug.println((doAdd? "Add":"Remove") + " SecureRandom algo " + s);
}
}
// used by new SecureRandom() to find out the default SecureRandom
// service for this provider
synchronized Service getDefaultSecureRandomService() {
Service getDefaultSecureRandomService() {
checkInitialized();
if (legacyChanged) {
prngAlgos = null;
ensureLegacyParsed();
}
if (prngAlgos != null && !prngAlgos.isEmpty()) {
if (!prngAlgos.isEmpty()) {
String algo = prngAlgos.iterator().next();
// IMPORTANT: use the Service obj returned by getService(...) call
// as providers may override putService(...)/getService(...) and
// return their own Service objects
return getService("SecureRandom", prngAlgos.iterator().next());
return getService("SecureRandom", algo);
}
return null;
@ -1473,12 +1507,9 @@ public abstract class Provider extends Properties {
for (String alias : s.getAliases()) {
serviceMap.remove(new ServiceKey(type, alias, false));
}
synchronized (this) {
removePropertyStrings(s);
if (type.equals("SecureRandom")) {
updateSecureRandomEntries(false, s.algorithm);
}
}
removePropertyStrings(s);
checkAndUpdateSecureRandom(type, algorithm, false);
}
// Wrapped String that behaves in a case insensitive way for equals/hashCode
@ -1686,6 +1717,13 @@ public abstract class Provider extends Properties {
aliases.add(alias);
}
private void removeAlias(String alias) {
if (aliases.isEmpty()) {
return;
}
aliases.remove(alias);
}
void addAttribute(String type, String value) {
if (attributes.isEmpty()) {
attributes = new HashMap<>(8);
@ -1693,6 +1731,17 @@ public abstract class Provider extends Properties {
attributes.put(new UString(type), value);
}
void removeAttribute(String type, String value) {
if (attributes.isEmpty()) {
return;
}
if (value == null) {
attributes.remove(new UString(type));
} else {
attributes.remove(new UString(type), value);
}
}
/**
* Construct a new service.
*