BlogJava-晓风残月-随笔分类-Java Primehttp://www.blogjava.net/jinglecat/category/11307.html新手上路zh-cnWed, 28 Feb 2007 12:59:04 GMTWed, 28 Feb 2007 12:59:04 GMT60java.sql.SQLException: [Microsoft][SQLServer 2000 Driver for JDBC]Error establishing socket.http://www.blogjava.net/jinglecat/archive/2006/06/10/51850.htmljinglecatjinglecatSat, 10 Jun 2006 07:35:00 GMThttp://www.blogjava.net/jinglecat/archive/2006/06/10/51850.htmlhttp://www.blogjava.net/jinglecat/comments/51850.htmlhttp://www.blogjava.net/jinglecat/archive/2006/06/10/51850.html#Feedback3http://www.blogjava.net/jinglecat/comments/commentRss/51850.htmlhttp://www.blogjava.net/jinglecat/services/trackbacks/51850.html使用MS Sql2000 for JDBC SP3连接MS Sql2000出现如下错误：

java.sql.SQLException:  [ Microsoft ][ SQLServer 2000 Driver for JDBC ] Error establishing socket.
    at com.microsoft.jdbc.base.BaseExceptions.createException(Unknown Source)
    at com.microsoft.jdbc.base.BaseExceptions.getException(Unknown Source)
    at com.microsoft.jdbc.base.BaseExceptions.getException(Unknown Source)
    at com.microsoft.jdbc.sqlserver.tds.TDSConnection.<init>(Unknown Source)
    at com.microsoft.jdbc.sqlserver.SQLServerImplConnection.open(Unknown Source)
    at com.microsoft.jdbc.base.BaseConnection.getNewImplConnection(Unknown Source)
    at com.microsoft.jdbc.base.BaseConnection.open(Unknown Source)
    at com.microsoft.jdbc.base.BaseDriver.connect(Unknown Source)
    at java.sql.DriverManager.getConnection(Unknown Source)
    at java.sql.DriverManager.getConnection(Unknown Source)
    at drawServlet.doGet(drawServlet.java: 50 )
    at drawServlet.doPost(drawServlet.java: 18 )
    at javax.servlet.http.HttpServlet.service(HttpServlet.java: 709 )
    at javax.servlet.http.HttpServlet.service(HttpServlet.java: 802 )
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java: 237 )
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java: 157 )
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java: 214 )
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java: 104 )
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java: 520 )
    at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java: 198 )
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java: 152 )
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java: 104 )
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java: 520 )
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java: 137 )
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java: 104 )
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java: 118 )
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java: 102 )
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java: 520 )
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java: 109 )
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java: 104 )
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java: 520 )
    at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java: 929 )
    at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java: 160 )
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java: 799 )
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java: 705 )
    at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java: 577 )
    at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java: 683 )
    at java.lang.Thread.run(Unknown Source)
java.sql.SQLException:  [ Microsoft ][ SQLServer 2000 Driver for JDBC ] End of stream was detected on a read.
    at com.microsoft.jdbc.base.BaseExceptions.createException(Unknown Source)
    at com.microsoft.jdbc.base.BaseExceptions.getException(Unknown Source)
    at com.microsoft.jdbc.sqlserver.tds.TDSRequest.processReply(Unknown Source)
    at com.microsoft.jdbc.sqlserver.SQLServerImplConnection.open(Unknown Source)
    at com.microsoft.jdbc.base.BaseConnection.getNewImplConnection(Unknown Source)
    at com.microsoft.jdbc.base.BaseConnection.open(Unknown Source)
    at com.microsoft.jdbc.base.BaseDriver.connect(Unknown Source)
    at java.sql.DriverManager.getConnection(Unknown Source)
    at java.sql.DriverManager.getConnection(Unknown Source)
    at drawServlet.doGet(drawServlet.java: 92 )
    at drawServlet.doPost(drawServlet.java: 18 )
    at javax.servlet.http.HttpServlet.service(HttpServlet.java: 709 )
    at javax.servlet.http.HttpServlet.service(HttpServlet.java: 802 )
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java: 237 )
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java: 157 )
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java: 214 )
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java: 104 )
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java: 520 )
    at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java: 198 )
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java: 152 )
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java: 104 )
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java: 520 )
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java: 137 )
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java: 104 )
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java: 118 )
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java: 102 )
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java: 520 )
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java: 109 )
    at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java: 104 )
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java: 520 )
    at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java: 929 )
    at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java: 160 )
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java: 799 )
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java: 705 )
    at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java: 577 )
    at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java: 683 )
    at java.lang.Thread.run(Unknown Source)

原因：由于开发环境是Win 2003 Server，故SQL 2000需要补丁包，不然在2k3下，SQL默认关闭了TCP连接
解决：打上SQL serverSP4 就OK了 

jinglecat 2006-06-10 15:35 发表评论
]]>java.io.IOException: open HTTP connection failedhttp://www.blogjava.net/jinglecat/archive/2006/05/20/47199.htmljinglecatjinglecatSat, 20 May 2006 11:04:00 GMThttp://www.blogjava.net/jinglecat/archive/2006/05/20/47199.htmlhttp://www.blogjava.net/jinglecat/comments/47199.htmlhttp://www.blogjava.net/jinglecat/archive/2006/05/20/47199.html#Feedback1http://www.blogjava.net/jinglecat/comments/commentRss/47199.htmlhttp://www.blogjava.net/jinglecat/services/trackbacks/47199.htmlerverybody，
       为什么偶将Applet的class文件放在WEB-INF\classes目录就加载不了，Java 控制台出现如下错误：

载入：找不到类 cqu.slmt412.rfds.applets.Zbasicall. class 。

java.lang.ClassNotFoundException: cqu.slmt412.rfds.applets.Zbasicall. class

    at sun.applet.AppletClassLoader.findClass(Unknown Source)

    at java.lang.ClassLoader.loadClass(Unknown Source)

    at sun.applet.AppletClassLoader.loadClass(Unknown Source)

    at java.lang.ClassLoader.loadClass(Unknown Source)

    at sun.applet.AppletClassLoader.loadCode(Unknown Source)

    at sun.applet.AppletPanel.createApplet(Unknown Source)

    at sun.plugin.AppletViewer.createApplet(Unknown Source)

    at sun.applet.AppletPanel.runLoader(Unknown Source)

    at sun.applet.AppletPanel.run(Unknown Source)

    at java.lang.Thread.run(Unknown Source)

Caused by: java.io.IOException: open HTTP connection failed.

    at sun.applet.AppletClassLoader.getBytes(Unknown Source)

    at sun.applet.AppletClassLoader.access$ 100 (Unknown Source)

    at sun.applet.AppletClassLoader$ 1 .run(Unknown Source)

    at java.security.AccessController.doPrivileged(Native Method)

      10  more
文件结构：
applet2.JPG
这是我的applet tag：
<applet code="cqu.slmt412.rfds.applets.Zbasicall.class" width=600 height=400>
即使加上codebase，也不行：
<applet code="cqu.slmt412.rfds.applets.Zbasicall.class" codebase="WEB-INF\classes" width=600 height=400>

但将包含class的目录放录直接放于应用程序路径就可以显示了，applet标签没有任何的改动。
可以运行的目录结构：
applet1.JPG

运行环境：
Windows 2003 sp1 ＋ IE6 ＋ Tomcat 5.02＋Java(TM) Plug-in: 版本 1.4.2_11

Why？



jinglecat 2006-05-20 19:04 发表评论
]]>int to bytes to inthttp://www.blogjava.net/jinglecat/archive/2006/05/19/46950.htmljinglecatjinglecatThu, 18 May 2006 20:43:00 GMThttp://www.blogjava.net/jinglecat/archive/2006/05/19/46950.htmlhttp://www.blogjava.net/jinglecat/comments/46950.htmlhttp://www.blogjava.net/jinglecat/archive/2006/05/19/46950.html#Feedback3http://www.blogjava.net/jinglecat/comments/commentRss/46950.htmlhttp://www.blogjava.net/jinglecat/services/trackbacks/46950.html新手上路，最好的见面礼莫过于资源分享了。

毕业设计中关键技术是数据压缩模块，数据传输的是字节数组，却没有发现Java库中现成的整型于字节数组的转换，虽然Integer包装类有toBinaryString()之类的静态方法使用，但是却无法直接满足要求一个整数与4个字节数组的对应，幸好String类有getBytes()几个重载方法使用，要不然真的就哭死了

记得net中就有BinConverter可以直接使用，而且实现了bytes与int16，int32，char等等多类型的转换，有点感慨，还是.net方便，呵呵

也许是偶还没有发现相关的Java库，google得也不深入，没办法，时间不等人，只好自己实现了一个，经测试，正负数都OK（PS：google到一个算法，比较搞笑，只有负数是正确）

 1 public   class  BitConverter  {
  2     
  3      public   static   byte [] getBytes( int  value)
  4      { 
  5          byte [] bytes  =   new   byte [ 4 ];
  6         bytes[ 0 ]  = ( byte )( value  >>   24  );
  7         bytes[ 1 ]  = ( byte )( (value  <<   8 )  >>   24  );
  8         bytes[ 2 ]  = ( byte )( (value  <<   16 )  >>   24  );
  9         bytes[ 3 ]  = ( byte )( (value  <<   24 )  >>   24  );        
 10          return  bytes;            
 11     }          
 12
13      public   static   int  toInt( byte [] bytes,  int  startIndex) {        
 14          int  value  =   0 ;
 15          for  ( int  j = startIndex;j < 4 ;j ++ )  {            
 16             value  =  (value  <<   8 )  |  (bytes[j]  &   0xFF );
 17         }         
 18          return  value;    
 19     }
20 }

只有int版本，有时间了再研究其他数据类型的了。

欢迎大家抛砖，期待更加便捷的算法。

jinglecat 2006-05-19 04:43 发表评论
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