Communications link failure Last packet sent to the server was 0 ms ago

Exception in thread "main" com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

Last packet sent to the server was 0 ms ago.

 at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

 at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)

 at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)

 at java.lang.reflect.Constructor.newInstance(Unknown Source)

 at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)

 at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)

 at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2120)

 at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:723)

 at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46)

 at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

 at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)

 at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)

 at java.lang.reflect.Constructor.newInstance(Unknown Source)

 at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)

 at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:302)

 at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:282)

 at java.sql.DriverManager.getConnection(Unknown Source)

 at java.sql.DriverManager.getConnection(Unknown Source)

 at test.JDBCTest.main(JDBCTest.java:12)

Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

Last packet sent to the server was 0 ms ago.

 at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

 at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)

 at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)

 at java.lang.reflect.Constructor.newInstance(Unknown Source)

 at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)

 at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)

 at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:335)

 at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2043)

 ... 12 more

Caused by: java.net.UnknownHostException: localhaost

 at java.net.Inet4AddressImpl.lookupAllHostAddr(Native Method)

 at java.net.InetAddress$1.lookupAllHostAddr(Unknown Source)

 at java.net.InetAddress.getAddressFromNameService(Unknown Source)

 at java.net.InetAddress.getAllByName0(Unknown Source)

 at java.net.InetAddress.getAllByName(Unknown Source)

 at java.net.InetAddress.getAllByName(Unknown Source)

 at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:243)

 at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:284)

 ... 13 more

开始的时候"jdbc:mysql://localhost:3306/world","admin","admin"写错了