SpigotCore_Main/src/de/steamwar/core/Core.java

@@ -71,7 +71,7 @@ public class Core extends JavaPlugin{
 
 	@Override
 	public void onDisable(){
-		SQL.closeConnection();
+		SQL.close();
 	}
 
 	public static Core getInstance() {

SpigotCore_Main/src/de/steamwar/sql/SQL.java

@@ -24,18 +24,18 @@ import org.bukkit.configuration.file.YamlConfiguration;
 
 import java.io.File;
 import java.sql.*;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.logging.Level;
 
 
 public class SQL {
-
 	private SQL(){}
 
-	private static final String host;
-	private static final String port;
-	private static final String database;
-	private static final String user;
-	private static final String password;
 	private static Connection con;
+	private static String url;
+	private static String user;
+	private static String password;
 
 	static{
 		File file = new File(Core.getInstance().getDataFolder(), "MySQL.yml");
@@ -44,20 +44,47 @@ public class SQL {
 		if(!file.exists())
 			throw new SecurityException("SQL-ConfigFile not found!");
 
-		host = config.getString("HOST");
-		port = config.getString("PORT");
-		database = config.getString("DATABASE");
+		url = "jdbc:mysql://" + config.getString("HOST") + ":" + config.getString("PORT") + "/" + config.getString("DATABASE");
 		user = config.getString("USER");
 		password = config.getString("PASSWORD");
 
 		connect();
 	}
-	
-	public static void closeConnection() {
+
+	private static void connect() {
+		try {
+			con = DriverManager.getConnection(url + "?autoreconnect=true", user, password);
+		} catch (SQLException e) {
+			throw new SecurityException("Could not start SQL connection", e);
+		}
+	}
+
+	public static void close() {
+		for (Statement statement : Statement.statements) {
+			try {
+				statement.st.close();
+			} catch (SQLException e) {
+				Core.getInstance().getLogger().log(Level.INFO, "Could not close statement", e);
+			}
+		}
+
 		try {
 			con.close();
-		}catch (SQLException e) {
-			throw new SecurityException("Could not close connection", e);
+		} catch (SQLException e) {
+			Core.getInstance().getLogger().log(Level.WARNING, "Could not close SQL-Connection", e);
+		}
+	}
+
+	private static void reset(SQLException e) {
+		Core.getInstance().getLogger().log(Level.WARNING, "SQL Exception thrown", e);
+		close();
+		connect();
+		try {
+			for (Statement statement : Statement.statements) {
+				statement.init();
+			}
+		} catch (SQLException ex) {
+			throw new SecurityException("Could not reprepare SQL Statements", ex);
 		}
 	}
 	
@@ -65,7 +92,7 @@ public class SQL {
 		try {
 			prepare(qry, objects).executeUpdate();
 		} catch (SQLException e) {
-			reconnect();
+			reset(e);
 			try {
 				prepare(qry, objects).executeUpdate();
 			} catch (SQLException ex) {
@@ -78,7 +105,7 @@ public class SQL {
 		try {
 			return prepare(qry, objects).executeQuery();
 		} catch (SQLException e) {
-			reconnect();
+			reset(e);
 			try {
 				return prepare(qry, objects).executeQuery();
 			} catch (SQLException ex) {
@@ -91,7 +118,7 @@ public class SQL {
 		try {
 			return con.createBlob();
 		} catch (SQLException e) {
-			reconnect();
+			reset(e);
 			try {
 				return con.createBlob();
 			} catch (SQLException ex) {
@@ -108,18 +135,66 @@ public class SQL {
 		return st;
 	}
 
-	private static void connect() {
-		try {
-			con = DriverManager.getConnection("jdbc:mysql://" + host + ":" + port + "/" + database + "?autoreconnect=true", user, password);
-			if(con.isClosed())
-				throw new SQLException("Could not connect to database!");
-		}catch (SQLException e) {
-			throw new SecurityException("No connection to database.", e);
+	public static class Statement {
+		private static final List<Statement> statements = new ArrayList<>();
+
+		private final String sql;
+		private PreparedStatement st;
+
+		Statement(String sql) {
+			this.sql = sql;
+			statements.add(this);
+			try {
+				init();
+			} catch (SQLException e) {
+				reset(e);
+			}
+		}
+
+		private synchronized void init() throws SQLException {
+			st = con.prepareStatement(sql);
+		}
+
+		<T> T select(ResultSetUser<T> user, Object... objects) {
+			return prepare(() -> {
+				ResultSet rs = st.executeQuery();
+				T result = user.use(rs);
+				rs.close();
+				return result;
+			}, objects);
+		}
+
+		void update(Object... objects) {
+			prepare(st::executeUpdate, objects);
+		}
+
+		private synchronized <T> T prepare(SQLRunnable<T> runnable, Object... objects) {
+			try {
+				setObjects(objects);
+				return runnable.run();
+			} catch (SQLException e) {
+				reset(e);
+				try {
+					setObjects(objects);
+					return runnable.run();
+				} catch (SQLException ex) {
+					throw new SecurityException("Could not execute SQL statement", ex);
+				}
+			}
+		}
+
+		private void setObjects(Object... objects) throws SQLException {
+			for (int i = 0; i < objects.length; i++) {
+				st.setObject(i + 1, objects[i]);
+			}
+		}
+
+		interface ResultSetUser<T> {
+			T use(ResultSet rs) throws SQLException;
+		}
+
+		private interface SQLRunnable<T> {
+			T run() throws SQLException;
 		}
 	}
-
-	private static void reconnect(){
-		closeConnection();
-		connect();
-	}
 }

SpigotCore_Main/src/de/steamwar/sql/Schematic.java

@@ -35,6 +35,8 @@ import java.util.zip.GZIPInputStream;
 
 public class Schematic {
 
+	private static final SQL.Statement getSchemsOfType = new SQL.Statement("SELECT DISTINCT s.SchemID, s.SchemName, s.SchemOwner, s.Item, s.SchemType, s.Rank, s.SchemFormat FROM Schematic s LEFT JOIN SchemMember sm ON sm.SchemName = s.SchemName AND sm.SchemOwner = s.SchemOwner WHERE s.SchemType = ? AND (s.SchemOwner = ? OR sm.Member = ?) ORDER BY s.SchemName");
+
 	private final int schemID;
 	private final String schemName;
 	private final int schemOwner;
@@ -118,12 +120,12 @@ public class Schematic {
 	}
 
 	public static List<Schematic> getSchemsOfType(int schemOwner, SchematicType schemType){
-		//Unsauber, dafür auch geaddede Schematics dabei
-		List<Schematic> schems = getSchemsAccessibleByUser(schemOwner);
-		for(int i = schems.size()-1; i >= 0; i--)
-			if(!schems.get(i).getSchemType().equals(schemType))
-				schems.remove(i);
-		return schems;
+		return getSchemsOfType.select(rs -> {
+			List<Schematic> schematics = new ArrayList<>();
+			while(rs.next())
+				schematics.add(new Schematic(rs));
+			return schematics;
+		}, schemType.toDB(), schemOwner, schemOwner);
 	}
 
 	public static List<Schematic> getAllSchemsOfType(SchematicType schemType){