请教：为什么eclipse export出来的jar，不能够访问WEB-INF/classes下面的类？

sweetBug 2013-06-28 02:40:53

如题，jar是用RAD导出的，应用服务器是websphere，求大神帮忙！

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sweetBug 2013-06-28

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引用 7 楼 ldh911 的回复:

[quote=引用 5 楼 sweetBug 的回复:] 共享库的类路径是在 Environment > Shared Libraries > Classpath 里面设置的，我用的websphere是6.0版本的。谢谢你给的链接！我上去看看

这个装载级别高多了，再下一级还有Websphere自带lib，再下一级还有APP-INF级别的lib和classes，再下一级才是WEB-INF级别的lib和classes。[/quote] 谢谢哈大侠，解决了问题，还学习到这么多哈！

MiceRice 2013-06-28

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引用 5 楼 sweetBug 的回复:

共享库的类路径是在 Environment > Shared Libraries > Classpath 里面设置的，我用的websphere是6.0版本的。谢谢你给的链接！我上去看看

这个装载级别高多了，再下一级还有Websphere自带lib，再下一级还有APP-INF级别的lib和classes，再下一级才是WEB-INF级别的lib和classes。

sweetBug 2013-06-28

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引用 4 楼 rumlee 的回复:

[quote=引用 3 楼 ldh911 的回复:] “共享库的类路径”是指哪里？装载级别低的，可以访问装载级别高的Class；反之则不行。 http://www.haogongju.net/art/2115488 http://he-wen.iteye.com/blog/766795

不要放到共享库，放到项目的lib路径下就可以了。[/quote] 果然是这样！！我放到项目的lib下面就可以了！谢谢两位了！！！

sweetBug 2013-06-28

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共享库的类路径是在 Environment > Shared Libraries > Classpath 里面设置的，我用的websphere是6.0版本的。谢谢你给的链接！我上去看看

rumlee 2013-06-28

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引用 3 楼 ldh911 的回复:

“共享库的类路径”是指哪里？装载级别低的，可以访问装载级别高的Class；反之则不行。 http://www.haogongju.net/art/2115488 http://he-wen.iteye.com/blog/766795

不要放到共享库，放到项目的lib路径下就可以了。

MiceRice 2013-06-28

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“共享库的类路径”是指哪里？装载级别低的，可以访问装载级别高的Class；反之则不行。 http://www.haogongju.net/art/2115488 http://he-wen.iteye.com/blog/766795

sweetBug 2013-06-28

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引用 1 楼 ldh911 的回复:

取决于你放在哪里或者说是以生么级别的ClassLoader装载的。

谢谢，我export的jar是放到共享库的类路径下的。很奇怪的是，web-inf/classes下面的类是可以访问这个jar里面的类，而反过来就访问不了。“以生么级别的ClassLoader装载”是什么意思呢，如果我需要jar可以访问到web-inf/classes的类，应该怎么生成呢？应该怎么样export?

MiceRice 2013-06-28

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取决于你放在哪里或者说是以生么级别的ClassLoader装载的。

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To avoid this problem, place classes that load native libraries outside of the web application, and ensure that the loadLibrary() call is executed only once during the lifetime of a particular JVM. ============= Bundled APIs: ============= A standard installation of Tomcat 7.0 makes all of the following APIs available for use by web applications (by placing them in "lib"): * annotations-api.jar (Annotations package) * catalina.jar (Tomcat Catalina implementation) * catalina-ant.jar (Tomcat Catalina Ant tasks) * catalina-ha.jar (High availability package) * catalina-tribes.jar (Group communication) * ecj-4.4.jar (Eclipse JDT Java compiler) * el-api.jar (EL 2.2 API) * jasper.jar (Jasper 2 Compiler and Runtime) * jasper-el.jar (Jasper 2 EL implementation) * jsp-api.jar (JSP 2.2 API) * servlet-api.jar (Servlet 3.0 API) * tomcat7-websocket.jar (WebSocket 1.1 implementation) * tomcat-api.jar (Interfaces shared by Catalina and Jasper) * tomcat-coyote.jar (Tomcat connectors and utility classes) * tomcat-dbcp.jar (package renamed database connection pool based on Commons DBCP) * tomcat-jdbc.jar (Tomcat's database connection pooling solution) * tomcat-util.jar (Various utilities) * websocket-api.jar (WebSocket 1.1 API) You can make additional APIs available to all of your web applications by putting unpacked classes into a "classes" directory (not created by default), or by placing them in JAR files in the "lib" directory. To override the XML parser implementation or interfaces, use the endorsed mechanism of the JVM. The default configuration defines JARs located in "endorsed" as endorsed. ================================================================ Web application reloading and static fields in shared libraries: ================================================================ Some shared libraries (many are part of the JDK) keep references to objects instantiated by the web application. To avoid class loading related problems (ClassCastExceptions, messages indicating that the classloader is stopped, etc.), the shared libraries state should be reinitialized. Something which might help is to avoid putting classes which would be referenced by a shared static field in the web application classloader, and putting them in the shared classloader instead (JARs should be put in the "lib" folder, and classes should be put in the "classes" folder). ================ Tomcat on Linux: ================ GLIBC 2.2 / Linux 2.4 users should define an environment variable: export LD_ASSUME_KERNEL=2.2.5 Redhat Linux 9.0 users should use the following setting to avoid stability problems: export LD_ASSUME_KERNEL=2.4.1 There are some Linux bugs reported against the NIO sendfile behavior, make sure you have a JDK that is up to date, or disable sendfile behavior in the Connector.
6427312: (fc) FileChannel.transferTo() throws IOException "system call interrupted"
5103988: (fc) FileChannel.transferTo should return -1 for EAGAIN instead throws IOException
6253145: (fc) FileChannel.transferTo on Linux fails when going beyond 2GB boundary
6470086: (fc) FileChannel.transferTo(2147483647, 1, channel) cause "Value too large" exception
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================================================================================ Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. ================================================================================ Apache Tomcat Version 8.0.15 Release Notes ========= CONTENTS: ========= * Dependency Changes * API Stability * Bundled APIs * Web application reloading and static fields in shared libraries * Security manager URLs * Symlinking static resources * Viewing the Tomcat Change Log * Cryptographic software notice * When all else fails =================== Dependency Changes: =================== Tomcat 8.0 is designed to run on Java SE 7 and later. ============== API Stability: ============== The public interfaces for the following classes are fixed and will not be changed at all during the remaining lifetime of the 8.x series: - All classes in the javax namespace The public interfaces for the following classes may be added to in order to resolve bugs and/or add new features. No existing interface method will be removed or changed although it may be deprecated. - org.apache.catalina.* (excluding sub-packages) Note: As Tomcat 8 matures, the above list will be added to. The list is not c

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