com.neko233.skilltree.global.lock.mysql.MysqlFuGlobalLock Maven / Gradle / Ivy
package com.neko233.skilltree.global.lock.mysql;
import com.neko233.skilltree.global.lock.GlobalLock;
import com.neko233.skilltree.global.lock.mysql.utils.JdbcHelper;
import lombok.SneakyThrows;
import lombok.extern.slf4j.Slf4j;
import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
/**
* FU 锁，可重入基于行锁，不支持行锁的无效或锁表，支持阻塞和非阻塞
*/
@Slf4j
public class MysqlFuGlobalLock implements GlobalLock {
public static final String CREATE_TABLE_SQL = " * create table if not exists neko233_global_lock_by_fu ( " +
" id int unsigned auto_increment primary key, " +
" lock_name varchar(100) not null, " +
" unique(lock_name) " +
" ) engine = innodb, charset uf8mb4 ";
public static final String SELECT_SQL = "select * from neko233_global_lock_by_fu where `lock_name`=? for update";
public static final String INSERT_SQL = "insert into neko233_global_lock_by_fu(lock_name) values(?)";
private final DataSource dataSource;
private ExecutorService threadPoolExecutor = Executors.newSingleThreadExecutor();
private Connection connection;
private String lockName;
public MysqlFuGlobalLock(DataSource dataSource,
String lockName) {
this.lockName = lockName;
this.dataSource = dataSource;
try (Connection conn = dataSource.getConnection();
PreparedStatement ps = conn.prepareStatement(CREATE_TABLE_SQL)) {
ps.execute();
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
@SneakyThrows
@Override
public void lock() {
PreparedStatement statement = null;
ResultSet resultSet = null;
try {
for (; ; ) {
connection = dataSource.getConnection();
connection.setAutoCommit(false);
statement = connection.prepareStatement(SELECT_SQL);
statement.setString(1, lockName);
resultSet = statement.executeQuery();
if (resultSet.next()) {
return;
}
JdbcHelper.gracefulClose(resultSet, statement, connection);
log.info("锁记录不存在，正在创建. lockName = {}", lockName);
Connection insertConnection = dataSource.getConnection();
PreparedStatement insertStatement = null;
try {
insertStatement = insertConnection.prepareStatement(INSERT_SQL);
insertStatement.setString(1, lockName);
if (insertStatement.executeUpdate() == 1) {
log.info("创建锁记录成功. lockName = {}", lockName);
}
} catch (Exception e) {
} finally {
JdbcHelper.gracefulClose(insertStatement, insertConnection);
}
}
} catch (Exception e) {
log.error("获取锁异常. lockName = {}", lockName, e);
} finally {
JdbcHelper.gracefulClose(resultSet, statement);
}
}
@Override
public boolean tryLock(long time,
TimeUnit unit) {
final Future future = threadPoolExecutor.submit(() -> {
try {
lock();
return 1;
} catch (Exception e) {
throw new RuntimeException(e);
}
});
try {
final Object o = future.get(time, unit);
if (o == null) {
future.cancel(true);
return false;
}
return true;
} catch (Exception e) {
return false;
}
}
@SneakyThrows
@Override
public void unlock() {
connection.commit();
connection.close();
}
}