HikariCP (#1851)

* jvm log forging

* jvm log forging

* jvm log forging

* log forging

* adding hikariCP module

* try-with-resources

* adding employee use case

* moving HikariCP to libraries

libraries/src/main/java/com/baeldung/hikaricp/DataSource.java

@@ -0,0 +1,48 @@
+package com.baeldung.hikaricp;
+
+import java.io.PrintWriter;
+import java.sql.Connection;
+import java.sql.SQLException;
+import java.util.Properties;
+
+import com.zaxxer.hikari.HikariConfig;
+import com.zaxxer.hikari.HikariDataSource;
+
+public class DataSource {
+
+	private static HikariConfig config = new HikariConfig();
+	private static HikariDataSource ds;
+
+	static {
+//		config = new HikariConfig("datasource.properties");
+		
+//		Properties props = new Properties();
+//		props.setProperty("dataSourceClassName", "org.postgresql.ds.PGSimpleDataSource");
+//		props.setProperty("dataSource.user", "postgres");
+//		props.setProperty("dataSource.password", "postgres");
+//		props.setProperty("dataSource.databaseName", "postgres");
+//		props.setProperty("dataSource.portNumber", "5432");
+//		props.setProperty("dataSource.serverName", "localhost");
+//		props.put("dataSource.logWriter", new PrintWriter(System.out));
+//		config = new HikariConfig(props);
+		
+		config.setJdbcUrl("jdbc:postgresql://localhost:5432/postgres");
+		config.setUsername("postgres");
+		config.setPassword("postgres");
+		config.addDataSourceProperty("cachePrepStmts", "true");
+		config.addDataSourceProperty("prepStmtCacheSize", "250");
+		config.addDataSourceProperty("prepStmtCacheSqlLimit", "2048");
+		ds = new HikariDataSource(config);
+		
+//		ds.setJdbcUrl("jdbc:postgresql://localhost:5432/postgres");
+//		ds.setUsername("postgres");
+//		ds.setPassword("postgres");
+	}
+
+	private DataSource() {}
+
+	public static Connection getConnection() throws SQLException {
+		return ds.getConnection();
+	}
+
+}