关于WAS当中FFDC报告error in opening zip file剖析及解决

关于WAS当中FFDC报告java.util.zip.ZipException: error in opening zip file剖析及解决

问题：
WAS下FFDC日志目录中出现如下的错误，打开zip文件错误

FFDC Exception:java.util.zip.ZipException SourceId:com.ibm.ws.classloader.ClassLoaderUtils.addDependents ProbeId:238 Reporter:java.lang.Class@7c537c91
java.util.zip.ZipException: error in opening zip file
	at java.util.zip.ZipFile.open(Native Method)
	at java.util.zip.ZipFile.<init>(ZipFile.java:114)
	at java.util.jar.JarFile.<init>(JarFile.java:133)
	at java.util.jar.JarFile.<init>(JarFile.java:70)
	at com.ibm.ws.classloader.ClassLoaderUtils.addDependents(ClassLoaderUtils.java:96)
	at com.ibm.ws.classloader.ClassLoaderUtils.addDependents(ClassLoaderUtils.java:143)
	at com.ibm.ws.classloader.ClassLoaderUtils.addDependentJars(ClassLoaderUtils.java:61)
	at com.ibm.ws.classloader.ClassGraph.<init>(ClassGraph.java:115)
	at com.ibm.ws.classloader.ClassLoaderManager.initialize(ClassLoaderManager.java:202)
	at com.ibm.ws.classloader.ClassLoaderManager.<init>(ClassLoaderManager.java:166)
	at com.ibm.ws.runtime.component.DeployedApplicationImpl.start(DeployedApplicationImpl.java:891)
	at com.ibm.ws.runtime.component.ApplicationMgrImpl.startApplication(ApplicationMgrImpl.java:740)
	at com.ibm.ws.runtime.component.ApplicationMgrImpl.start(ApplicationMgrImpl.java:2092)
	at com.ibm.ws.runtime.component.CompositionUnitMgrImpl.start(CompositionUnitMgrImpl.java:437)
	at com.ibm.ws.runtime.component.CompositionUnitImpl.start(CompositionUnitImpl.java:122)
	at com.ibm.ws.runtime.component.CompositionUnitMgrImpl.start(CompositionUnitMgrImpl.java:380)
	at com.ibm.ws.runtime.component.CompositionUnitMgrImpl.access$300(CompositionUnitMgrImpl.java:105)
	at com.ibm.ws.runtime.component.CompositionUnitMgrImpl$CUInitializer.run(CompositionUnitMgrImpl.java:928)
	at com.ibm.wsspi.runtime.component.WsComponentImpl$_AsynchInitializer.run(WsComponentImpl.java:349)
	at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:1527)

那到底是哪个文件在打开时发生错误了呢？一头雾水了吧，汗。。。估计你会。。。

分析：
1、通过对文件的排查，确认排除了应用程序中引用jar文件损坏的可能性以及由于jar文件权限设置导致无法读取的可能性

2、打开跟踪日志级别进行剖析

Application servers > memXXX > Logging and Tracing > Change log detail levels

设置ClassLoaderUtils跟踪级别如下

*=info: com.ibm.ws.classloader.ClassLoaderUtils=finest

重新启动后，在trace.log里可以发现如下信息

 0000001e ClassLoaderUt >  addDependents Entry
/home/xxx/lib/struts/commons-logging.jar
 0000001e ClassLoaderUt 3   dependent classpath detected: log4j.jar log4j-core.jar
 0000001e ClassLoaderUt 3   adding /home/xxx/lib/struts/log4j.jar
 0000001e ClassLoaderUt >  addDependents Entry
/home/xxx/lib/struts/log4j.jar
 0000001e FfdcProvider  I com.ibm.ws.ffdc.impl.FfdcProvider logIncident FFDC1003I: FFDC Incident emitted on /usr/IBM/WebSphere/AppServer/profiles/XXX/logs/ffdc/memXXX_f3c3750_08.12.23_16.26.42.85048008.txt com.ibm.ws.classloader.ClassLoaderUtils.addDependents 238
 0000001e ClassLoaderUt 3   WARNING: could not open /home/xxx/lib/struts/log4j.jar : error in opening zip file
 0000001e ClassLoaderUt <  addDependents Exit
/home/xxx/lib/struts/log4j.jar
 0000001e ClassLoaderUt 3   adding /home/xxx/lib/struts/log4j-core.jar
 0000001e ClassLoaderUt >  addDependents Entry
/home/xxx/lib/struts/log4j-core.jar
 0000001e ClassLoaderUt 3   WARNING: could not open /home/xxx/lib/struts/log4j-core.jar : error in opening zip file
 0000001e ClassLoaderUt <  addDependents Exit
/home/xxx/lib/struts/log4j-core.jar
 0000001e ClassLoaderUt <  addDependents Exit
/home/xxx/lib/struts/commons-logging.jar
......
 0000001e ClassLoaderUt >  addDependents Entry
/home/xxx/lib/struts/struts.jar
 0000001e ClassLoaderUt 3   dependent classpath detected:  commons-beanutils.jar commons-collections.jar commons-digester.jar commons-logging.jar commons-validator.jar jakarta-oro.jar struts-legacy.jar
 0000001e ClassLoaderUt 3   adding /home/xxx/lib/struts/jakarta-oro.jar
 0000001e ClassLoaderUt >  addDependents Entry
/home/xxx/lib/struts/jakarta-oro.jar
 0000001e ClassLoaderUt 3   WARNING: could not open /home/xxx/lib/struts/jakarta-oro.jar : error in opening zip file
 0000001e ClassLoaderUt <  addDependents Exit
/home/xxx/lib/struts/jakarta-oro.jar
 0000001e ClassLoaderUt 3   adding /home/xxx/lib/struts/struts-legacy.jar
 0000001e ClassLoaderUt >  addDependents Entry
/home/xxx/lib/struts/struts-legacy.jar
 0000001e ClassLoaderUt 3   WARNING: could not open /home/xxx/lib/struts/struts-legacy.jar : error in opening zip file
 0000001e ClassLoaderUt <  addDependents Exit
/home/xxx/lib/struts/struts-legacy.jar
 0000001e ClassLoaderUt <  addDependents Exit
......

继续分析：
首先，可以确认的是WARNING所报的是正确的，因为可以通过确认所依赖的log4j.jar log4j-core.jar jakarta-oro.jar struts-legacy.jar之类的文件不存在。
其次，这些不存在的包是由谁依赖并需要加载的，通过日志的层次关系可以知道，commons-logging.jar需要log4j.jar log4j-core.jar，struts.jar需要jakarta-oro.jar struts-legacy.jar
这样唯一的可能就是各自的jar包中META-INF\MANIFEST.MF里声明了这些jar的依赖关系了。

打开commons-logging.jar，发现其中的META-INF\MANIFEST.MF里包含了
Class-Path: log4j.jar log4j-core.jar

打开struts.jar，发现其中的META-INF\MANIFEST.MF里包含了
Class-Path:  commons-beanutils.jar commons-collections.jar commons-dig
ester.jar commons-logging.jar commons-validator.jar jakarta-oro.jar s
truts-legacy.jar

于是真相大白了，解决的办法要么增加相应版本所依赖的jar包，要么就是简单地删除Class-Path，根据应用程序的需要进行确认并使用之，[color=red]建议用前者进行解决。要么就升级这些组件包。[/color]

代码解读

ClassLoaderUtils.java
public static String[] addDependentJars(String paths[])
{
    ArrayList newPaths = new ArrayList(Arrays.asList(paths));
    for(int i = 0; i < paths.length; i++)
        if(paths[i].toLowerCase().endsWith(".jar"))
            addDependents(paths[i], newPaths);

    String result[] = new String[newPaths.size()];
    result = (String[])(String[])newPaths.toArray(result);
    return result;
}

private static void addDependents(String jarFileName, List classpath)
{
// ...省略。。。
jar = new JarFile(jarFileName);// 错误在这一行
manifest = jar.getManifest();
attrs = manifest.getMainAttributes();
dependents = attrs.getValue(java.util.jar.Attributes.Name.CLASS_PATH);// 获取依赖包路径
StringTokenizer tokens = new StringTokenizer(dependents, " ");
do
{
    if(!tokens.hasMoreTokens())
        break;
    String nextDependent = tokens.nextToken();
    String nextDependentFullPath = (new StringBuilder()).append(prefix).append(nextDependent).
    if(PathUtils.listAddNoDup(classpath, nextDependentFullPath))
    {
        addDependents(nextDependentFullPath, classpath); // 迭代加载之
    }
} while(true);
// ...省略。。。
在catch代码块中
catch(ZipException ze)
{
    Manager.Ffdc.log(ze, ClassLoaderUtils.class, "com.ibm.ws.classloader.ClassLoaderUtils.addDependents", "238" + jarFileName);
    if(debugEnabled)
        Tr.debug(tc, (new StringBuilder()).append("WARNING: could not open ").append(jarFileName).append(" : ").append(ze.getLocalizedMessage()).toString());
}
catch(IOException ioe)
{
    Manager.Ffdc.log(ioe, ClassLoaderUtils.class, "com.ibm.ws.classloader.ClassLoaderUtils.addDependents", "246");
    if(debugEnabled)
        Tr.debug(tc, (new StringBuilder()).append("WARNING: I/O exception ").append(jarFileName).append(" : ").append(ioe.getLocalizedMessage()).toString());
}

不厚道，在Manager.Ffdc.log里把jarFileName也打印出来，就更容易知道是什么问题了。
可见打印出有意义的信息对于分析问题是多少的重要。。。

附带信息：将commons-logging.jar与struts.jar与Spring 2.5.5发布所带的包进行对比分析，发现Spring带的commons-logging.jar包没有带有Class-Path这个条目。

Manifest-Version: 1.0
Created-By: Apache Ant 1.5.1
Extension-Name: org.apache.commons.logging
Specification-Vendor: Apache Software Foundation
Specification-Version: 1.0
Implementation-Vendor: Apache Software Foundation
Implementation-Version: 1.0.3
Class-Path: log4j.jar log4j-core.jar

对比

Manifest-Version: 1.0
Archiver-Version: Plexus Archiver
Created-By: Apache Maven
Built-By: dlg01
Build-Jdk: 1.4.2_16
Implementation-Title: Commons Logging
Implementation-Vendor: Apache Software Foundation
Implementation-Vendor-Id: org.apache
Implementation-Version: 1.1.1
Specification-Title: Commons Logging
Specification-Vendor: Apache Software Foundation
Specification-Version: 1.0
X-Compile-Source-JDK: 1.2
X-Compile-Target-JDK: 1.1
Extension-Name: org.apache.commons.logging

注意实现的版本问题是不同的

struct.jar包的条目内容不同

Manifest-Version: 1.0
Created-By: Apache Ant 1.5.1
Extension-Name: Struts Framework
Specification-Title: Struts Framework
Specification-Vendor: Apache Software Foundation
Specification-Version: 1.1
Implementation-Title: Struts Framework
Implementation-Vendor: Apache Software Foundation
Implementation-Vendor-Id: org.apache
Implementation-Version: 1.1
Class-Path:  commons-beanutils.jar commons-collections.jar commons-dig
 ester.jar commons-logging.jar commons-validator.jar jakarta-oro.jar s
 truts-legacy.jar

对比

Manifest-Version: 1.0
Ant-Version: Apache Ant 1.6.1
Created-By: 1.3.1_04-b02 (Sun Microsystems Inc.)
Extension-Name: Struts Framework
Specification-Title: Struts Framework
Specification-Vendor: The Apache Software Foundation
Specification-Version: 1.2.9
Implementation-Title: Struts Framework
Implementation-Vendor: The Apache Software Foundation
Implementation-Vendor-Id: org.apache
Implementation-Version: 1.2.9
Class-Path:  commons-beanutils.jar commons-digester.jar commons-fileup
 load.jar commons-logging.jar commons-validator.jar jakarta-oro.jar

也要注意实现的版本问题是不同的