feat: create JsonType.java

src/main/java/de/codemakers/database/types/JsonType.java

@@ -0,0 +1,130 @@
+/*
+ *    Copyright 2021 Paul Hagedorn (Panzer1119)
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+package de.codemakers.database.types;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.hibernate.HibernateException;
+import org.hibernate.engine.spi.SharedSessionContractImplementor;
+import org.hibernate.usertype.UserType;
+
+import java.io.*;
+import java.nio.charset.StandardCharsets;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Types;
+import java.util.Objects;
+
+public class JsonType<T extends Serializable> implements UserType<T> {
+
+    private final Class<T> type;
+
+    public JsonType(Class<T> type) {
+        this.type = type;
+    }
+
+    public Class<T> getType() {
+        return type;
+    }
+
+    @Override
+    public int[] sqlTypes() {
+        return new int[] {Types.JAVA_OBJECT};
+    }
+
+    @Override
+    public Class<T> returnedClass() {
+        return getType();
+    }
+
+    @Override
+    public boolean equals(Object x, Object y) throws HibernateException {
+        return Objects.equals(x, y);
+    }
+
+    @Override
+    public int hashCode(Object x) throws HibernateException {
+        return Objects.hashCode(x);
+    }
+
+    @Override
+    public T nullSafeGet(ResultSet resultSet, int position, SharedSessionContractImplementor session, Object owner) throws SQLException {
+        final String cellContent = resultSet.getString(position);
+        if (cellContent == null) {
+            return null;
+        }
+        try {
+            final ObjectMapper mapper = new ObjectMapper();
+            return mapper.readValue(cellContent.getBytes(StandardCharsets.UTF_8), returnedClass());
+        } catch (Exception e) {
+            throw new RuntimeException(String.format("Failed to convert String to %s: %s", returnedClass().getName(), e.getMessage()), e);
+        }
+    }
+
+    @Override
+    public void nullSafeSet(PreparedStatement preparedStatement, T value, int index, SharedSessionContractImplementor session) throws SQLException {
+        if (value == null) {
+            preparedStatement.setNull(index, Types.OTHER);
+            return;
+        }
+        try {
+            final ObjectMapper objectMapper = new ObjectMapper();
+            final StringWriter stringWriter = new StringWriter();
+            objectMapper.writeValue(stringWriter, value);
+            stringWriter.flush();
+            preparedStatement.setObject(index, stringWriter.toString(), Types.OTHER);
+        } catch (Exception e) {
+            throw new RuntimeException(String.format("Failed to convert %s to String: %s", returnedClass().getName(), e.getMessage()), e);
+        }
+    }
+
+    @Override
+    public Object deepCopy(Object value) throws HibernateException {
+        try {
+            final ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
+            final ObjectOutputStream objectOutputStream = new ObjectOutputStream(byteArrayOutputStream);
+            objectOutputStream.writeObject(value);
+            objectOutputStream.flush();
+            objectOutputStream.close();
+            byteArrayOutputStream.close();
+            final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(byteArrayOutputStream.toByteArray());
+            return new ObjectInputStream(byteArrayInputStream).readObject();
+        } catch (ClassNotFoundException | IOException e) {
+            throw new HibernateException(e);
+        }
+    }
+
+    @Override
+    public boolean isMutable() {
+        return true;
+    }
+
+    @Override
+    public Serializable disassemble(Object value) throws HibernateException {
+        return (Serializable) deepCopy(value);
+    }
+
+    @Override
+    public Object assemble(Serializable cached, Object owner) throws HibernateException {
+        return deepCopy(cached);
+    }
+
+    @Override
+    public Object replace(Object original, Object target, Object owner) throws HibernateException {
+        return deepCopy(original);
+    }
+}