导入了mysql驱动包 按老师说的打了一次，琢磨好久 还是报错，求救

Question

com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception: 

** BEGIN NESTED EXCEPTION ** 

com.mysql.jdbc.CommunicationsException

MESSAGE: Communications link failure due to underlying exception: 

** BEGIN NESTED EXCEPTION ** 

java.io.EOFException

MESSAGE: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost.

STACKTRACE:

java.io.EOFException: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost.

at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1997)

at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2411)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2916)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:885)

at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1300)

at com.mysql.jdbc.Connection.createNewIO(Connection.java:2775)

at com.mysql.jdbc.Connection.<init>(Connection.java:1555)

at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)

at java.sql.DriverManager.getConnection(DriverManager.java:571)

at java.sql.DriverManager.getConnection(DriverManager.java:215)

at DButil.DButil.main(DButil.java:20)

** END NESTED EXCEPTION **

Last packet sent to the server was 7 ms ago.

STACKTRACE:

com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception: 

** BEGIN NESTED EXCEPTION ** 

java.io.EOFException

MESSAGE: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost.

STACKTRACE:

java.io.EOFException: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost.

at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1997)

at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2411)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2916)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:885)

at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1300)

at com.mysql.jdbc.Connection.createNewIO(Connection.java:2775)

at com.mysql.jdbc.Connection.<init>(Connection.java:1555)

at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)

at java.sql.DriverManager.getConnection(DriverManager.java:571)

at java.sql.DriverManager.getConnection(DriverManager.java:215)

at DButil.DButil.main(DButil.java:20)

** END NESTED EXCEPTION **

Last packet sent to the server was 7 ms ago.

at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2622)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2916)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:885)

at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1300)

at com.mysql.jdbc.Connection.createNewIO(Connection.java:2775)

at com.mysql.jdbc.Connection.<init>(Connection.java:1555)

at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)

at java.sql.DriverManager.getConnection(DriverManager.java:571)

at java.sql.DriverManager.getConnection(DriverManager.java:215)

at DButil.DButil.main(DButil.java:20)

** END NESTED EXCEPTION **

Last packet sent to the server was 7 ms ago.

at com.mysql.jdbc.Connection.createNewIO(Connection.java:2847)

at com.mysql.jdbc.Connection.<init>(Connection.java:1555)

at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)

at java.sql.DriverManager.getConnection(DriverManager.java:571)

at java.sql.DriverManager.getConnection(DriverManager.java:215)

at DButil.DButil.main(DButil.java:20)

Answer 1

你的URL后面多了个?号