src/de/steamwar/sql/Field.java

@@ -0,0 +1,39 @@
+/*
+ * This file is a part of the SteamWar software.
+ *
+ * Copyright (C) 2022  SteamWar.de-Serverteam
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.sql;
+
+public class Field {
+
+    private final String identifier;
+    private final Class<?> type;
+
+    public Field(String identifier, Class<?> type) {
+        this.identifier = identifier;
+        this.type = type;
+    }
+
+    public String identifier() {
+        return identifier;
+    }
+
+    public Class<?> type() {
+        return type;
+    }
+}

src/de/steamwar/sql/Row.java

@@ -0,0 +1,35 @@
+/*
+ * This file is a part of the SteamWar software.
+ *
+ * Copyright (C) 2022  SteamWar.de-Serverteam
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.sql;
+
+public class Row {
+
+    private final Table table;
+    private Object[] values;
+
+    public Row(Table table, Object[] values) {
+        this.table = table;
+        this.values = values;
+    }
+
+    void update(Field field, Object value) {
+
+    }
+}

src/de/steamwar/sql/Statement.java

@@ -111,6 +111,10 @@ public class Statement implements AutoCloseable {
         withConnection(PreparedStatement::executeUpdate, objects);
     }
 
+    public String getSql() {
+        return sql;
+    }
+
     private <T> T withConnection(SQLRunnable<T> runnable, Object... objects) {
         Connection connection = aquireConnection();
 

src/de/steamwar/sql/Table.java

@@ -0,0 +1,87 @@
+/*
+ * This file is a part of the SteamWar software.
+ *
+ * Copyright (C) 2022  SteamWar.de-Serverteam
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.steamwar.sql;
+
+import java.util.*;
+import java.util.logging.Level;
+import java.util.stream.Collectors;
+
+public class Table {
+
+    private final String name;
+    private final Field key;
+    private final Field[] fields;
+
+    private final Map<Field, Statement> selectBy = new HashMap<>();
+
+    public Table(String name, Field key, Field... fields) {
+        this.name = name;
+        this.key = key;
+        this.fields = fields;
+    }
+
+    public Row selectSingle(Field field, Object value) {
+        return select(rs -> {
+            if(!rs.next())
+                return null;
+
+            Object[] values = new Object[fields.length];
+            for(int i = 0; i < fields.length; i++) {
+                values[i] = fields[i].type().cast(rs.getObject(i));
+            }
+
+            if(rs.next())
+                SQLConfig.impl.getLogger().log(Level.WARNING, "Statement returned more than one result " + selectBy.get(field).getSql() + " for value " + value);
+
+            return new Row(this, values);
+        }, field, value);
+    }
+
+    public List<Row> selectMulti(Field field, Object value) {
+        return select(rs -> {
+            List<Row> result = new ArrayList<>();
+            while(rs.next()) {
+                Object[] values = new Object[fields.length];
+                for(int i = 0; i < fields.length; i++) {
+                    values[i] = fields[i].type().cast(rs.getObject(i));
+                }
+
+                result.add(new Row(this, values));
+            }
+            return result;
+        }, field, value);
+    }
+
+    public void create() {
+        //TODO and alter table
+    }
+
+    public Field getKey() {
+        return key;
+    }
+
+    private <T> T select(Statement.ResultSetUser<T> u, Field field, Object value) {
+        Statement statement;
+        synchronized (selectBy) {
+            statement = selectBy.computeIfAbsent(field, f -> new Statement("SELECT " + Arrays.stream(fields).map(Field::identifier).collect(Collectors.joining(", ")) + " FROM " + name + " WHERE " + field.identifier() + " = ?"));
+        }
+        return statement.select(u, value);
+    }
+}