重装MySQL后出错/java与javac版本不一致

MYSQL:
C:/Documents and Settings>cd c:/mysql/bin

C:/mysql/bin>mysql -u root -p
Enter password:
ERROR 2003: Can't connect to MySQL server on 'localhost' (10061)

C:/mysql/bin>mysql -u root -p0000
ERROR 2003: Can't connect to MySQL server on 'localhost' (10061)

C:/mysql/bin>mysqld-nt

C:/mysql/bin>mysql -u root -p
Enter password: ****
ERROR 2003: Can't connect to MySQL server on 'localhost' (10061)

C:/mysql/bin>mysqld

C:/mysql/bin>mysql -u root -p
Enter password:
ERROR 2003: Can't connect to MySQL server on 'localhost' (10061)

C:/mysql/bin>net start mysql
发生系统错误 3。

系统找不到指定的路径。


C:/mysql/bin>mysqlshow
mysqlshow: Can't connect to MySQL server on 'localhost' (10061)
  ++++++++++++++++++++++++++++++++++++
解决办法：

C:/mysql/bin>mysqld-nt -install
The service already exists!
The current server installed:

C:/mysql/bin>mysqld-nt -remove
Service successfully removed.

C:/mysql/bin>mysqld -install
Service successfully installed.

C:/mysql/bin>mysqld

C:/mysql/bin>mysqld --console
InnoDB: The first specified data file ./ibdata1 did not exist:
InnoDB: a new database to be created!
040712 18:19:27 InnoDB: Setting file ./ibdata1 size to 10 MB
InnoDB: Database physically writes the file full: wait...
040712 18:19:27 InnoDB: Log file ./ib_logfile0 did not exist: new to be created
........

mysqld: ready for connections.
Version: '4.0.20a-debug' socket: '' port: 3306

+++++++++++++++++
C:/mysql/bin>mysqld --skip-name-resolve

C:/Documents and Settings/sunshine>cd c:/mysql/bin

C:/mysql/bin>mysqld

C:/mysql/bin>mysql
Welcome to the MySQL monitor. Commands end with ; or /g.
Your MySQL connection id is 1 to server version: 4.0.20a-debug

Type 'help;' or '/h' for help. Type '/c' to clear the buffer.

mysql>
    +++++++++++++++++++++++++

    I:/Java_work> java ChartTester
    Exception in thread "main" java.lang.UnsupportedClassVersionError: ChartTester (Unsupp
    orted major.minor version 49.0)
        at java.lang.ClassLoader.defineClass0(Native Method)
        at java.lang.ClassLoader.defineClass(Unknown Source)
        at java.security.SecureClassLoader.defineClass(Unknown Source)
        at java.net.URLClassLoader.defineClass(Unknown Source)
        at java.net.URLClassLoader.access$100(Unknown Source)
        .........

I:/Java_work>

出现这种错误是因为你的java (jvm)版本低，
C:/Documents and Settings/Administrator>java -version
java version "1.4.2_03"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_03-b02)
Java HotSpot(TM) Client VM (build 1.4.2_03-b02, mixed mode)

C:/Documents and Settings/Administrator>
而

C:/Documents and Settings/Administrator>javac -version

javac version "1.5.0_0"
这是由于你的path 环境变量设置的问题，
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

解决办法，确实使你使用的java 版本保持在最前，即放到最前边，
C:/Documents and Settings/Administrator>java -version
java version "1.5.0"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0-b64)
Java HotSpot(TM) Client VM (build 1.5.0-b64, mixed mode, sharing)

C:/Documents and Settings/Administrator>

OK了

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

若运行java命令时提示exception in thread "main" java.lang.NoClassDefFoundErroe:的异常
 一般情况说明你的classpath里没有加入 . 即当前目录
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Windows下AVI文件无法删除?试试先建立一个文本文件，然后把这个文件和avi一起选中，然后删除。