使用ConcurrentHashMap避免新增或查找User、Role时产生的同步问题

lealone-db/src/main/java/org/lealone/db/Database.java

@@ -729,8 +729,8 @@ public synchronized void removeMeta(ServerSession session, int id) {
     }
 
     @SuppressWarnings("unchecked")
-    private HashMap<String, DbObject> getMap(int type) {
-        HashMap<String, ? extends DbObject> result;
+    private Map<String, DbObject> getMap(int type) {
+        Map<String, ? extends DbObject> result;
         switch (type) {
         case DbObject.USER:
             result = Auth.getUsersMap();
@@ -792,7 +792,7 @@ public synchronized void addDatabaseObject(ServerSession session, DbObject obj)
         if (id > 0 && !starting) {
             checkWritingAllowed();
         }
-        HashMap<String, DbObject> map = getMap(obj.getType());
+        Map<String, DbObject> map = getMap(obj.getType());
         // if (obj.getType() == DbObject.USER) {
         // User user = (User) obj;
         // if (user.isAdmin() && systemUser.getName().equals(SYSTEM_USER_NAME)) {
@@ -1233,7 +1233,7 @@ private synchronized void updateMetaAndFirstLevelChildren(ServerSession session,
     public synchronized void renameDatabaseObject(ServerSession session, DbObject obj, String newName) {
         checkWritingAllowed();
         int type = obj.getType();
-        HashMap<String, DbObject> map = getMap(type);
+        Map<String, DbObject> map = getMap(type);
         if (SysProperties.CHECK) {
             if (!map.containsKey(obj.getName())) {
                 DbException.throwInternalError("not found: " + obj.getName());
@@ -1305,7 +1305,7 @@ public synchronized void removeDatabaseObject(ServerSession session, DbObject ob
         checkWritingAllowed();
         String objName = obj.getName();
         int type = obj.getType();
-        HashMap<String, DbObject> map = getMap(type);
+        Map<String, DbObject> map = getMap(type);
         if (SysProperties.CHECK && !map.containsKey(objName)) {
             DbException.throwInternalError("not found: " + objName);
         }

lealone-db/src/main/java/org/lealone/db/LealoneDatabase.java

@@ -18,11 +18,11 @@
 package org.lealone.db;
 
 import java.util.ArrayList;
-import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.Properties;
+import java.util.concurrent.ConcurrentHashMap;
 
-import org.lealone.common.util.New;
 import org.lealone.db.auth.Auth;
 
 /**
@@ -47,7 +47,7 @@ public static LealoneDatabase getInstance() {
         return INSTANCE;
     }
 
-    private final HashMap<String, Database> databases = New.hashMap();
+    private final ConcurrentHashMap<String, Database> databases = new ConcurrentHashMap<>();
 
     private LealoneDatabase() {
         super(0, NAME, null);
@@ -74,7 +74,7 @@ protected void initTraceSystem(ConnectionInfo ci) {
         Auth.init(this);
     }
 
-    public synchronized Database findDatabase(String dbName) {
+    public Database findDatabase(String dbName) {
         return databases.get(dbName);
     }
 
@@ -85,15 +85,15 @@ synchronized Database createDatabase(String dbName, ConnectionInfo ci) {
         return db;
     }
 
-    synchronized void closeDatabase(String dbName) {
+    void closeDatabase(String dbName) {
         databases.remove(dbName);
     }
 
-    synchronized List<Database> getDatabases() {
+    List<Database> getDatabases() {
         return new ArrayList<>(databases.values());
     }
 
-    synchronized HashMap<String, Database> getDatabasesMap() {
+    Map<String, Database> getDatabasesMap() {
         return databases;
     }
 }

lealone-db/src/main/java/org/lealone/db/auth/Auth.java

@@ -18,7 +18,8 @@
 package org.lealone.db.auth;
 
 import java.util.ArrayList;
-import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 import org.lealone.api.ErrorCode;
 import org.lealone.common.message.DbException;
@@ -40,9 +41,9 @@ public class Auth {
      */
     private static final String SYSTEM_USER_NAME = "DBA";
 
-    private static final HashMap<String, Role> roles = New.hashMap();
-    private static final HashMap<String, User> users = New.hashMap();
-    private static final HashMap<String, Right> rights = New.hashMap();
+    private static final ConcurrentHashMap<String, Role> roles = new ConcurrentHashMap<>();
+    private static final ConcurrentHashMap<String, User> users = new ConcurrentHashMap<>();
+    private static final ConcurrentHashMap<String, Right> rights = new ConcurrentHashMap<>();
 
     private static User systemUser;
     private static Role publicRole;
@@ -82,7 +83,7 @@ public static ArrayList<Role> getAllRoles() {
         return New.arrayList(roles.values());
     }
 
-    public static HashMap<String, Role> getRolesMap() {
+    public static Map<String, Role> getRolesMap() {
         return roles;
     }
 
@@ -116,15 +117,15 @@ public static ArrayList<User> getAllUsers() {
         return New.arrayList(users.values());
     }
 
-    public static HashMap<String, User> getUsersMap() {
+    public static Map<String, User> getUsersMap() {
         return users;
     }
 
     public static ArrayList<Right> getAllRights() {
         return New.arrayList(rights.values());
     }
 
-    public static HashMap<String, Right> getRightsMap() {
+    public static Map<String, Right> getRightsMap() {
         return rights;
     }
 }

lealone-sql/src/main/java/org/lealone/sql/StatementWrapper.java

@@ -364,7 +364,7 @@ public boolean isDDL() {
 
     @Override
     public boolean isBatch() {
-        return statement.isDDL();
+        return statement.isBatch();
     }
 
     @Override

lealone-sql/src/main/java/org/lealone/sql/ddl/CreateUser.java

@@ -77,7 +77,7 @@ static void setPassword(User user, ServerSession session, Expression password) {
         char[] passwordChars = pwd == null ? new char[0] : pwd.toCharArray();
         byte[] userPasswordHash;
         String userName = user.getName();
-        if (userName.length() == 0 && passwordChars.length == 0) {
+        if (userName.isEmpty() && passwordChars.length == 0) {
             userPasswordHash = new byte[0];
         } else {
             userPasswordHash = SHA256.getKeyPasswordHash(userName, passwordChars);
@@ -89,7 +89,6 @@ static void setPassword(User user, ServerSession session, Expression password) {
     public int update() {
         session.getUser().checkAdmin();
         session.commit(true);
-        Database db = LealoneDatabase.getInstance();
         if (Auth.findRole(userName) != null) {
             throw DbException.get(ErrorCode.ROLE_ALREADY_EXISTS_1, userName);
         }
@@ -99,6 +98,7 @@ public int update() {
             }
             throw DbException.get(ErrorCode.USER_ALREADY_EXISTS_1, userName);
         }
+        Database db = LealoneDatabase.getInstance();
         int id = getObjectId(db);
         User user = new User(db, id, userName, false);
         user.setAdmin(admin);