Support concurrent loading of Config for different namespaces (#29)

apollo-client/src/main/java/com/ctrip/framework/apollo/internals/DefaultConfigManager.java

@@ -30,21 +30,30 @@
  * @author Jason Song([email protected])
  */
 public class DefaultConfigManager implements ConfigManager {
-  private ConfigFactoryManager m_factoryManager;
+  private final ConfigFactoryManager m_factoryManager;
 
-  private Map<String, Config> m_configs = Maps.newConcurrentMap();
-  private Map<String, ConfigFile> m_configFiles = Maps.newConcurrentMap();
+  private final Map<String, Config> m_configs = Maps.newConcurrentMap();
+  private final Map<String, ConfigFile> m_configFiles = Maps.newConcurrentMap();
+  private final Map<String, Object> m_configLocks = Maps.newConcurrentMap();
+  private final Map<String, Object> m_configFileLocks = Maps.newConcurrentMap();
 
   public DefaultConfigManager() {
     m_factoryManager = ApolloInjector.getInstance(ConfigFactoryManager.class);
   }
 
   @Override
   public Config getConfig(String namespace) {
+    String lockKey = buildLockKey(namespace);
+    Object lock = m_configLocks.get(lockKey);
+    if (lock == null) {
+      synchronized (lockKey) {
+        lock = m_configLocks.computeIfAbsent(lockKey, k -> new Object());
+      }
+    }
     Config config = m_configs.get(namespace);
 
     if (config == null) {
-      synchronized (this) {
+      synchronized (lock) {
         config = m_configs.get(namespace);
 
         if (config == null) {
@@ -62,10 +71,17 @@ public Config getConfig(String namespace) {
   @Override
   public ConfigFile getConfigFile(String namespace, ConfigFileFormat configFileFormat) {
     String namespaceFileName = String.format("%s.%s", namespace, configFileFormat.getValue());
+    String lockKey = buildLockKey(namespaceFileName);
+    Object lock = m_configFileLocks.get(lockKey);
+    if (lock == null) {
+      synchronized (lockKey) {
+        lock = m_configFileLocks.computeIfAbsent(lockKey, k -> new Object());
+      }
+    }
     ConfigFile configFile = m_configFiles.get(namespaceFileName);
 
     if (configFile == null) {
-      synchronized (this) {
+      synchronized (lock) {
         configFile = m_configFiles.get(namespaceFileName);
 
         if (configFile == null) {
@@ -79,4 +95,8 @@ public ConfigFile getConfigFile(String namespace, ConfigFileFormat configFileFor
 
     return configFile;
   }
+
+  private String buildLockKey(String factor) {
+    return (String.format("%s.%s", getClass().getName(), factor)).intern();
+  }
 }