问题
Im trying to use HikariCP with a mariaDB database but i getting the next error when im trying to initialize.
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at com.zaxxer.hikari.pool.HikariPool.initializeConnections(HikariPool.java:581) ~[Dubilets-1.0-SNAPSHOT.jar:?]
at com.zaxxer.hikari.pool.HikariPool.<init>(HikariPool.java:152) ~[Dubilets-1.0-SNAPSHOT.jar:?]
at com.zaxxer.hikari.HikariDataSource.<init>(HikariDataSource.java:73) ~[Dubilets-1.0-SNAPSHOT.jar:?]
at eu.elraro.dubilets.storage.Database.<init>(Database.java:69) [Dubilets-1.0-SNAPSHOT.jar:?]
at eu.elraro.dubilets.storage.MariaDBDatabase.<init>(MariaDBDatabase.java:18) [Dubilets-1.0-SNAPSHOT.jar:?]
at eu.elraro.dubilets.Dubilets.realizaConexion(Dubilets.java:168) [Dubilets-1.0-SNAPSHOT.jar:?]
at eu.elraro.dubilets.Dubilets.inicializaVariables(Dubilets.java:164) [Dubilets-1.0-SNAPSHOT.jar:?]
at eu.elraro.dubilets.Dubilets.onEnable(Dubilets.java:69) [Dubilets-1.0-SNAPSHOT.jar:?]
at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:321) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:340) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:405) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugin(CraftServer.java:357) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
at org.bukkit.craftbukkit.v1_8_R3.CraftServer.enablePlugins(CraftServer.java:317) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
at net.minecraft.server.v1_8_R3.MinecraftServer.s(MinecraftServer.java:414) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
at net.minecraft.server.v1_8_R3.MinecraftServer.k(MinecraftServer.java:378) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
at net.minecraft.server.v1_8_R3.MinecraftServer.a(MinecraftServer.java:333) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
at net.minecraft.server.v1_8_R3.DedicatedServer.init(DedicatedServer.java:263) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:524) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
at java.lang.Thread.run(Thread.java:745) [?:1.8.0_66]
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
My MariaDBDatabase class:
public class MariaDBDatabase extends Database {
/*
* Construct a MySQL database instance.
*
* @param host Host/IP of the MySQL database.
* @param port Port of the MySQL database.
* @param database Database wanted to be access.
* @param username Username to be authenticated with.
* @param password Password for the user authentication.
* @param plugin Plugin for the schedulers to be assigned to.
*/
public MariaDBDatabase(String host, int port, String database, String username, String password, JavaPlugin plugin) {
super("org.mariadb.jdbc.MySQLDataSource", "jdbc:mysql://" + host + ":" + port + "/" + database, username, password, plugin);
}
My Database class:
public abstract class Database {
private String jdbcURL;
private HikariDataSource dataSource;
private JavaPlugin plugin;
/**
* Construct a database instance.
*
* @param className The class name used to get the driver.
* @param jdbcURL A JDBC url to use for connecting.
* @param username Username to connect with.
* @param password Password to authenticate username.
* @param plugin A plugin instance for the schedulers to be assigned to.
*/
public Database(String className, String jdbcURL, String username, String password, JavaPlugin plugin) {
this.jdbcURL = jdbcURL;
this.plugin = plugin;
try {
Bukkit.getLogger().log(Level.INFO, "Initializing the connection pool ... ");
Class.forName(className);
} catch (ClassNotFoundException e) {
Bukkit.getLogger().log(Level.SEVERE, "Exception when trying to initialize the connection pool",e);
return;
}
HikariConfig config = new HikariConfig();
config.setDriverClassName(className);
config.setJdbcUrl(jdbcURL);
config.setUsername(username);
config.setPassword(password);
//config.setLeakDetectionThreshold(10000);
//config.setMaximumPoolSize(10);
config.setMaximumPoolSize(5);
config.setConnectionTestQuery("SELECT 1");
config.setPoolName("HikariCP");
try {
dataSource = new HikariDataSource(config);
Bukkit.getLogger().log(Level.INFO, "Connection pool initialized successfully.");
} catch (Exception e) {
Bukkit.getLogger().log(Level.SEVERE, "Exception when trying to initialize the connection pool",e);
}
}
/**
* Connects the data pool to the database.
*/
public boolean connect() {
return isConnected();
}
/**
* Disconnects (shutdown) the data pool and all connections.
*/
public void disconnect() {
dataSource.shutdown();
}
/**
* Query the database and return a cached result.
*
* @param query The statement to be queried.
* @return Cached rowset returned from query.
*/
public CachedRowSet query(final PreparedStatement preparedStatement) {
CachedRowSet rowSet = null;
if (isConnected()) {
try {
ExecutorService exe = Executors.newCachedThreadPool();
Future<CachedRowSet> future = exe.submit(new Callable<CachedRowSet>() {
public CachedRowSet call() {
try {
ResultSet resultSet = preparedStatement.executeQuery();
CachedRowSet cachedRowSet = new CachedRowSetImpl();
cachedRowSet.populate(resultSet);
resultSet.close();
preparedStatement.getConnection().close();
if (cachedRowSet.next()) {
return cachedRowSet;
}
} catch (SQLException e) {
e.printStackTrace();
}
return null;
}
});
if (future.get() != null) {
rowSet = future.get();
}
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
}
return rowSet;
}
/**
* Execute a query
*
* @param preparedStatement query to be executed.
*/
public void execute(final PreparedStatement preparedStatement) {
if (isConnected()) {
Bukkit.getScheduler().runTaskAsynchronously(plugin, new Runnable() {
public void run() {
try {
preparedStatement.execute();
preparedStatement.getConnection().close();
} catch (SQLException e) {
e.printStackTrace();
}
}
});
}
}
/**
* Prepare a statement
*
* @param query Query to be prepared.
* @param vars Variables to be replaced from ?.
* @return a prepared statement.
*/
public PreparedStatement prepareStatement(String query, Object... vars) {
try {
PreparedStatement preparedStatement = getConnection().prepareStatement(query);
int x = 0;
if (query.contains("?") && vars.length != 0) {
for (Object var : vars) {
x++;
if (var instanceof String) {
preparedStatement.setString(x, (String) var);
} else {
preparedStatement.setInt(x, (Integer) var);
}
}
}
return preparedStatement;
} catch (SQLException e) {
e.printStackTrace();
}
return null;
}
/**
* Get a connection from the data pool
*
* @return a connection.
*/
public Connection getConnection() {
try {
return dataSource.getConnection();
} catch (SQLException e) {
e.printStackTrace();
}
return null;
}
/**
* Check if the data pool is connected.
*
* @return connected Whether the data pool is connected or not.
*/
public boolean isConnected() {
try {
dataSource.getConnection();
} catch (SQLException e) {
return false;
}
return true;
}
My pom.xml
<project
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>eu.elraro.dubilets</groupId>
<artifactId>Dubilets</artifactId>
<version>1.0-SNAPSHOT</version>
<repositories>
<repository>
<id>bungeecord-repo</id>
<url>https://oss.sonatype.org/content/repositories/snapshots</url>
</repository>
</repositories>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>2.3</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
</execution>
</executions>
<configuration>
<createDependencyReducedPom>false</createDependencyReducedPom>
<artifactSet>
<includes>
<include>org.slf4j:*</include>
<include>com.zaxxer:*</include>
<include>org.mariadb.jdbc:*</include>
<include>org.javassist:javassist</include>
</includes>
</artifactSet>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<!--Spigot API -->
<dependency>
<groupId>org.spigotmc</groupId>
<artifactId>spigot-api</artifactId>
<version>1.8.8-R0.1-SNAPSHOT</version>
<scope>provided</scope>
</dependency>
<!--Bukkit API -->
<dependency>
<groupId>org.bukkit</groupId>
<artifactId>bukkit</artifactId>
<version>1.8.8-R0.1-SNAPSHOT</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>com.zaxxer</groupId>
<artifactId>HikariCP</artifactId>
<version>2.4.1</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>org.mariadb.jdbc</groupId>
<artifactId>mariadb-java-client</artifactId>
<version>1.2.3</version>
</dependency>
<dependency>
<groupId>com.gmail.filoghost</groupId>
<artifactId>holographic-displays-api</artifactId>
<version>2.1.7</version>
<scope>system</scope>
<systemPath>${basedir}/lib/HolographicDisplaysAPI_v2.1.7.jar</systemPath>
</dependency>
</dependencies>
回答1:
Don't set both the dataSourceClassname and jdbcUrl ... they are mutually exclusive. For simplicity, I recommend the jdbcUrl.
来源：https://stackoverflow.com/questions/33816105/hikaricp-connection-error