mtg-decks-downloader

Cache.java (2845B)

 package fr.kevincorvisier.mtg.dd;
 
 import java.io.BufferedReader;
 import java.io.BufferedWriter;
 import java.io.File;
 import java.io.IOException;
 import java.io.StringReader;
 import java.net.URL;
 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 
 import javax.annotation.Nullable;
 
 import org.apache.commons.io.output.StringBuilderWriter;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Service;
 
 import fr.kevincorvisier.mtg.utils.mtgo.MagicOnlineDeckContent;
 import fr.kevincorvisier.mtg.utils.mtgo.MagicOnlineFileReader;
 import fr.kevincorvisier.mtg.utils.mtgo.MagicOnlineFileWriter;
 import jakarta.validation.constraints.NotNull;
 import lombok.NonNull;
 import lombok.extern.slf4j.Slf4j;
 
 @Slf4j
 @Service
 public class Cache
 {
 	private static final String QUERY_INITIALIZE = "CREATE TABLE IF NOT EXISTS `decks` (`url` TEXT PRIMARY KEY,`content` TEXT);";
 
 	private final Connection connection;
 
 	public Cache(@Value("${cache.database}") final String file) throws SQLException
 	{
 		if (file == null)
 			throw new NullPointerException("Property cache.database must be present and have a value");
 
 		new File(file).getParentFile().mkdirs();
 
 		connection = DriverManager.getConnection("jdbc:sqlite:" + file);
 		initialize();
 	}
 
 	private void initialize() throws SQLException
 	{
 		try (PreparedStatement ps = connection.prepareStatement(QUERY_INITIALIZE))
 		{
 			ps.executeUpdate();
 		}
 	}
 
 	@Nullable
 	public MagicOnlineDeckContent findByUrl(@NonNull @NotNull final URL url)
 	{
 		final String content;
 
 		try (PreparedStatement ps = connection.prepareStatement("SELECT content FROM decks WHERE url = ?"))
 		{
 			ps.setString(1, url.toString());
 			final ResultSet rs = ps.executeQuery();
 
 			if (!rs.next())
 				return null;
 
 			content = rs.getString("content");
 		}
 		catch (final SQLException e)
 		{
 			log.error("findByUrl: url={}", url, e);
 			return null;
 		}
 
 		try (BufferedReader reader = new BufferedReader(new StringReader(content)))
 		{
 			return MagicOnlineFileReader.read(reader);
 		}
 		catch (final NumberFormatException | IOException e)
 		{
 			// Cached content is not valid, return null
 			return null;
 		}
 	}
 
 	public void save(@NonNull @NotNull final URL url, @NonNull @NotNull final MagicOnlineDeckContent content) throws SQLException, IOException
 	{
 		final StringBuilder builder = new StringBuilder();
 
 		try (BufferedWriter writer = new BufferedWriter(new StringBuilderWriter(builder)))
 		{
 			MagicOnlineFileWriter.write(writer, content);
 		}
 
 		try (PreparedStatement ps = connection.prepareStatement("INSERT INTO `decks` (`url`, `content`) VALUES (?, ?);"))
 		{
 			ps.setString(1, url.toString());
 			ps.setString(2, builder.toString());
 			ps.executeUpdate();
 		}
 	}
 }