use lock when the database is single-threaded only

Author: HSGamer

storage/simple/src/main/java/me/hsgamer/topper/storage/simple/supplier/MySqlStorageSupplier.java

@@ -3,10 +3,7 @@
 import me.hsgamer.hscore.database.Setting;
 import me.hsgamer.hscore.database.client.sql.java.JavaSqlClient;
 import me.hsgamer.hscore.database.driver.mysql.MySqlDriver;
-import me.hsgamer.hscore.logger.common.LogLevel;
 
-import java.sql.Connection;
-import java.sql.SQLException;
 import java.util.Collections;
 import java.util.List;
 import java.util.function.Consumer;
@@ -21,19 +18,8 @@ public MySqlStorageSupplier(Consumer<Setting> databaseSettingConsumer) {
     }
 
     @Override
-    protected Connection getConnection() throws SQLException {
-        Connection connection = client.getConnection();
-        connection.setAutoCommit(false);
-        return connection;
-    }
-
-    @Override
-    protected void flushConnection(Connection connection) {
-        try {
-            connection.close();
-        } catch (SQLException e) {
-            logger.log(LogLevel.ERROR, "Failed to close connection", e);
-        }
+    public JavaSqlClient getClient() {
+        return client;
     }
 
     @Override

storage/simple/src/main/java/me/hsgamer/topper/storage/simple/supplier/SqlStorageSupplier.java

@@ -1,6 +1,7 @@
 package me.hsgamer.topper.storage.simple.supplier;
 
 import me.hsgamer.hscore.database.client.sql.BatchBuilder;
+import me.hsgamer.hscore.database.client.sql.SqlClient;
 import me.hsgamer.hscore.database.client.sql.StatementBuilder;
 import me.hsgamer.hscore.logger.common.LogLevel;
 import me.hsgamer.hscore.logger.common.Logger;
@@ -19,23 +20,48 @@ public abstract class SqlStorageSupplier implements DataStorageSupplier {
     protected final Logger logger = LoggerProvider.getLogger(getClass());
     private final Lock lock = new ReentrantLock();
 
-    protected abstract Connection getConnection() throws SQLException;
+    protected abstract SqlClient<?> getClient();
 
-    protected abstract void flushConnection(Connection connection);
-
-    protected boolean shouldLockWhenModify() {
+    protected boolean isSingleThread() {
         return false;
     }
 
     protected abstract List<String> toSaveStatement(String name, String[] keyColumns, String[] valueColumns);
 
     protected abstract List<Object[]> toSaveValues(Object[] keys, Object[] values);
 
+    private Connection getConnection() throws SQLException {
+        Connection connection = getClient().getConnection();
+        connection.setAutoCommit(false);
+        return connection;
+    }
+
+    private void flushConnection(Connection connection) {
+        try {
+            connection.close();
+        } catch (SQLException e) {
+            logger.log(LogLevel.ERROR, "Failed to close connection", e);
+        }
+    }
+
+    private void lock() {
+        if (isSingleThread()) {
+            lock.lock();
+        }
+    }
+
+    private void unlock() {
+        if (isSingleThread()) {
+            lock.unlock();
+        }
+    }
+
     @Override
     public <K, V> DataStorage<K, V> getStorage(String name, ValueConverter<K> keyConverter, ValueConverter<V> valueConverter) {
         return new DataStorage<K, V>() {
             @Override
             public Map<K, V> load() {
+                lock();
                 Connection connection = null;
                 try {
                     connection = getConnection();
@@ -52,11 +78,13 @@ public Map<K, V> load() {
                     if (connection != null) {
                         flushConnection(connection);
                     }
+                    unlock();
                 }
             }
 
             @Override
             public Optional<V> load(K key) {
+                lock();
                 Connection connection = null;
                 try {
                     connection = getConnection();
@@ -88,14 +116,13 @@ public Optional<V> load(K key) {
                     if (connection != null) {
                         flushConnection(connection);
                     }
+                    unlock();
                 }
             }
 
             @Override
             public Optional<Modifier<K, V>> modify() {
-                if (shouldLockWhenModify()) {
-                    lock.lock();
-                }
+                lock();
                 try {
                     Connection connection = getConnection();
                     Modifier<K, V> modifier = new Modifier<K, V>() {
@@ -154,9 +181,7 @@ public void commit() {
                                 logger.log(LogLevel.ERROR, "Failed to commit", e);
                             } finally {
                                 flushConnection(connection);
-                                if (shouldLockWhenModify()) {
-                                    lock.unlock();
-                                }
+                                unlock();
                             }
                         }
 
@@ -168,21 +193,21 @@ public void rollback() {
                                 logger.log(LogLevel.ERROR, "Failed to rollback", e);
                             } finally {
                                 flushConnection(connection);
-                                if (shouldLockWhenModify()) {
-                                    lock.unlock();
-                                }
+                                unlock();
                             }
                         }
                     };
                     return Optional.of(modifier);
                 } catch (SQLException e) {
                     logger.log(LogLevel.ERROR, "Failed to get connection", e);
+                    unlock();
                     return Optional.empty();
                 }
             }
 
             @Override
             public void onRegister() {
+                lock();
                 Connection connection = null;
                 try {
                     connection = getConnection();
@@ -224,6 +249,7 @@ public void onRegister() {
                     if (connection != null) {
                         flushConnection(connection);
                     }
+                    unlock();
                 }
             }
         };

storage/simple/src/main/java/me/hsgamer/topper/storage/simple/supplier/SqliteStorageSupplier.java

@@ -3,18 +3,14 @@
 import me.hsgamer.hscore.database.Setting;
 import me.hsgamer.hscore.database.client.sql.java.JavaSqlClient;
 import me.hsgamer.hscore.database.driver.sqlite.SqliteFileDriver;
-import me.hsgamer.hscore.logger.common.LogLevel;
 
 import java.io.File;
-import java.sql.Connection;
 import java.util.Arrays;
 import java.util.List;
-import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.Consumer;
 
 public class SqliteStorageSupplier extends SqlStorageSupplier {
     private final JavaSqlClient client;
-    private final AtomicReference<Connection> connectionReference = new AtomicReference<>();
 
     public SqliteStorageSupplier(Consumer<Setting> databaseSettingConsumer, File baseHolder) {
         Setting setting = Setting.create(new SqliteFileDriver(baseHolder));
@@ -23,30 +19,12 @@ public SqliteStorageSupplier(Consumer<Setting> databaseSettingConsumer, File bas
     }
 
     @Override
-    protected Connection getConnection() {
-        return connectionReference.updateAndGet(connection -> {
-            try {
-                if (connection == null || connection.isClosed()) {
-                    Connection clientConnection = client.getConnection();
-                    clientConnection.setAutoCommit(false);
-                    return clientConnection;
-                } else {
-                    return connection;
-                }
-            } catch (Exception e) {
-                logger.log(LogLevel.ERROR, "Failed to get the connection", e);
-                return null;
-            }
-        });
+    public JavaSqlClient getClient() {
+        return client;
     }
 
     @Override
-    protected void flushConnection(Connection connection) {
-        // EMPTY
-    }
-
-    @Override
-    protected boolean shouldLockWhenModify() {
+    protected boolean isSingleThread() {
         return true;
     }
 
@@ -115,16 +93,4 @@ protected List<Object[]> toSaveValues(Object[] keys, Object[] values) {
                 updateValues
         );
     }
-
-    @Override
-    public void disable() {
-        Connection connection = connectionReference.getAndSet(null);
-        try {
-            if (connection != null && !connection.isClosed()) {
-                connection.close();
-            }
-        } catch (Exception e) {
-            logger.log(LogLevel.ERROR, "Failed to close the connection", e);
-        }
-    }
 }