当我在pom.xml中添加库依赖项时，jetty servlet容器无法正常运行

时间：2019-05-19 10:45:42

标签： java maven jetty web-development-server

我有一个带有spring的简单Java Web应用程序。 然后我添加了

    <dependency>
        <groupId>org.web3j</groupId>
        <artifactId>core</artifactId>
        <version>4.2.0</version>
    </dependency>
    <dependency>
        <groupId>org.web3j</groupId>
        <artifactId>crypto</artifactId>
        <version>4.2.0</version>
    </dependency>
    <dependency>
        <groupId>org.web3j</groupId>
        <artifactId>abi</artifactId>
        <version>4.2.0</version>
    </dependency>

到pom.xml

现在执行mvn jetty:run后，我得到了（几分钟后将打印出来）

[WARNING] Failed startup of context o.e.j.m.p.JettyWebAppContext@4784efd9{/crowdfunding,file:/C:/Users/d/eclipse-jee-workspace/crowdfunding/src/main/webapp/,STARTING}{file:/C:/Users/d/eclipse-jee-workspace/crowdfunding/src/main/webapp/}
java.lang.Exception: Timeout scanning annotations
    at org.eclipse.jetty.annotations.AnnotationConfiguration.scanForAnnotations (AnnotationConfiguration.java:577)
    at org.eclipse.jetty.annotations.AnnotationConfiguration.configure (AnnotationConfiguration.java:447)

在我的浏览器上出现503错误

1 个答案:

答案 0 :(得分：1)

默认扫描将等待60秒（1分钟）以扫描所有WEB-INF/classes和WEB-INF/lib/*.jar文件。

可以将其配置为更长。 但是，如果已经花了那么长时间，那么您可能已经...

  • 非常慢的计算机（您没有说）
  • 一大堆WEB-INF/lib条目（您也没有告诉我们）
  • 您的WEB-INF/lib个条目中的一个错误（一个错误的jar文件，实际上很常见）
  • 与Web应用程序冲突的服务器类的配置（在嵌入式码头的使用上比在独立jetty-home的使用上更常见）
  • 使用自定义类加载器对WebAppContext进行配置（不建议这样做，如果您确实有此配置，则说明您是一个人，因为此处的所有内容均假定为正常的WebAppClassloader）
  • 您的WebAppContext的配置会反转Servlet标准父加载程序的优先级（如果您已设置此setParentLoaderPriority()，请将该调用注释掉，然后重试）

让我们假设您的jar文件错误或依赖项冲突。

这3个依赖项引入了什么？

$ mvn dependency:tree
...(snip)...
[INFO] --- maven-dependency-plugin:2.8:tree (default-cli) @ huge-war ---
[INFO] org.eclipse.jetty.demo:huge-war:war:1.0-SNAPSHOT
[INFO] +- javax.servlet:javax.servlet-api:jar:3.1.0:provided
[INFO] +- org.web3j:core:jar:4.2.0:compile
[INFO] |  +- org.web3j:tuples:jar:4.2.0:compile
[INFO] |  +- com.github.jnr:jnr-unixsocket:jar:0.21:compile
[INFO] |  |  +- com.github.jnr:jnr-ffi:jar:2.1.9:compile
[INFO] |  |  |  +- com.github.jnr:jffi:jar:1.2.17:compile
[INFO] |  |  |  +- com.github.jnr:jffi:jar:native:1.2.16:runtime
[INFO] |  |  |  +- org.ow2.asm:asm:jar:5.0.3:compile
[INFO] |  |  |  +- org.ow2.asm:asm-commons:jar:5.0.3:compile
[INFO] |  |  |  +- org.ow2.asm:asm-analysis:jar:5.0.3:compile
[INFO] |  |  |  +- org.ow2.asm:asm-tree:jar:5.0.3:compile
[INFO] |  |  |  +- org.ow2.asm:asm-util:jar:5.0.3:compile
[INFO] |  |  |  +- com.github.jnr:jnr-a64asm:jar:1.0.0:compile
[INFO] |  |  |  \- com.github.jnr:jnr-x86asm:jar:1.0.2:compile
[INFO] |  |  +- com.github.jnr:jnr-constants:jar:0.9.11:compile
[INFO] |  |  +- com.github.jnr:jnr-enxio:jar:0.19:compile
[INFO] |  |  \- com.github.jnr:jnr-posix:jar:3.0.47:compile
[INFO] |  +- com.squareup.okhttp3:okhttp:jar:3.8.1:compile
[INFO] |  |  \- com.squareup.okio:okio:jar:1.13.0:compile
[INFO] |  +- com.squareup.okhttp3:logging-interceptor:jar:3.8.1:compile
[INFO] |  +- io.reactivex.rxjava2:rxjava:jar:2.2.2:compile
[INFO] |  |  \- org.reactivestreams:reactive-streams:jar:1.0.2:compile
[INFO] |  +- org.java-websocket:Java-WebSocket:jar:1.3.8:compile
[INFO] |  +- com.fasterxml.jackson.core:jackson-databind:jar:2.8.5:compile
[INFO] |  |  +- com.fasterxml.jackson.core:jackson-annotations:jar:2.8.0:compile
[INFO] |  |  \- com.fasterxml.jackson.core:jackson-core:jar:2.8.5:compile
[INFO] |  \- org.slf4j:slf4j-api:jar:1.7.25:compile
[INFO] +- org.web3j:crypto:jar:4.2.0:compile
[INFO] |  +- org.web3j:rlp:jar:4.2.0:compile
[INFO] |  \- org.web3j:utils:jar:4.2.0:compile
[INFO] |     \- org.bouncycastle:bcprov-jdk15on:jar:1.60:compile
[INFO] \- org.web3j:abi:jar:4.2.0:compile

unixsocket类将在WebApp中出现问题，因为Servlet容器带来的类加载器隔离和各种保护意味着当在ServletContext的锁定环境中执行时，这些本机类/库将无法工作。

但这不会阻止webapp启动，只会阻止运行时IPC / UnixSocket行为。

我还看到了org.ow2.asm:asm:jar:5.0.3:compile，它很旧。

Jetty随asm 7.0一起提供

$ ls -la ~/code/jetty/distros/jetty-home-9.4.18.v20190429/lib/annotations/
total 316
drwxr-xr-x  2 joakim joakim   4096 May  1 13:09 ./
drwxr-xr-x 14 joakim joakim   4096 May  1 13:09 ../
-rw-r--r--  1 joakim joakim 113676 Nov  2  2018 asm-7.0.jar
-rw-r--r--  1 joakim joakim  33317 Nov  2  2018 asm-analysis-7.0.jar
-rw-r--r--  1 joakim joakim  79850 Nov  2  2018 asm-commons-7.0.jar
-rw-r--r--  1 joakim joakim  50399 Nov  2  2018 asm-tree-7.0.jar
-rw-r--r--  1 joakim joakim  26430 Jan 31 15:09 javax.annotation-api-1.3.jar

取决于启动Jetty的方式，这可能是初始化和注释/字节码扫描问题的根源。 asm 5.0和asm 7.0不完全二进制兼容（至少从Jetty的需求/用途的角度来看）

总而言之，关于您要查询的3个<dependency>条目的已解决/有效的依存关系列表，没有untowards。

因此，让我们看看如果您尝试仅部署具有这三个依赖项的Web应用程序，并完成注释扫描... 

$ cat start.ini
--module=http
jetty.http.port=8080
--module=deploy
--module=annotations

$ ls -la webapps/
total 10500
drwxr-xr-x 2 joakim joakim     4096 May 19 10:59 ./
drwxr-xr-x 6 joakim joakim     4096 May 19 10:58 ../
-rw-r--r-- 1 joakim joakim 10742370 May 19 10:58 demo-with-w3j-libs.war

$ java -jar ~/code/jetty/distros/jetty-home-9.4.18.v20190429/start.jar 
java -jar ~/code/jetty/distros/jetty-home-9.4.18.v20190429/start.jar
2019-05-19 11:11:02.993:INFO::main: Logging initialized @397ms to org.eclipse.jetty.util.log.StdErrLog
2019-05-19 11:11:03.182:INFO:oejs.Server:main: jetty-9.4.18.v20190429; built: 2019-04-29T20:42:08.989Z; git: e1bc35120a6617ee3df052294e433f3a25ce7097; jvm 11.0.3+7
2019-05-19 11:11:03.195:INFO:oejdp.ScanningAppProvider:main: Deployment monitor [file:///home/joakim/code/jetty/stackoverflow/huge-war/webapps/] at interval 1
2019-05-19 11:11:03.896:INFO:oeja.AnnotationConfiguration:main: Scanning elapsed time=436ms
2019-05-19 11:11:03.902:INFO:oejw.StandardDescriptorProcessor:main: NO JSP Support for /demo-with-w3j-libs, did not find org.eclipse.jetty.jsp.JettyJspServlet
2019-05-19 11:11:03.911:INFO:oejs.session:main: DefaultSessionIdManager workerName=node0
2019-05-19 11:11:03.911:INFO:oejs.session:main: No SessionScavenger set, using defaults
2019-05-19 11:11:03.912:INFO:oejs.session:main: node0 Scavenging every 660000ms
2019-05-19 11:11:03.929:INFO:oejsh.ContextHandler:main: Started o.e.j.w.WebAppContext@75437611{Demo of a WebApp with a large WEB-INF/lib,/demo-with-w3j-libs,file:///tmp/jetty-0.0.0.0-8080-demo-with-w3j-libs.war-_demo-with-w3j-libs-any-5411225940231111244.dir/webapp/,AVAILABLE}{/demo-with-w3j-libs.war}
2019-05-19 11:11:04.236:INFO:oeja.AnnotationConfiguration:main: Scanning elapsed time=184ms
2019-05-19 11:11:04.237:INFO:oejw.StandardDescriptorProcessor:main: NO JSP Support for /huge-war, did not find org.eclipse.jetty.jsp.JettyJspServlet
2019-05-19 11:11:04.240:INFO:oejsh.ContextHandler:main: Started o.e.j.w.WebAppContext@6f7923a5{Demo of a WebApp with a large WEB-INF/lib,/huge-war,file:///tmp/jetty-0.0.0.0-8080-huge-war.war-_huge-war-any-2121417525584312936.dir/webapp/,AVAILABLE}{/huge-war.war}
2019-05-19 11:11:04.295:INFO:oejs.AbstractConnector:main: Started ServerConnector@52c3cb31{HTTP/1.1,[http/1.1]}{0.0.0.0:8080}
2019-05-19 11:11:04.295:INFO:oejs.Server:main: Started @1700ms

是的，如我所料，它将初始化就好了。实际上，扫描该WAR（在我的计算机上）只花了不到184ms的时间.. 

2019-05-19 11:11:04.236:INFO:oeja.AnnotationConfiguration:main: Scanning elapsed time=184ms

也许您的初始化可以告诉您正在发生的事情。

在org.eclipse.jetty.annotations和org.eclipse.jetty.webapp都启用DEBUG的情况下运行，并查看是否存在任何异常。还请注意注释扫描报告的时间安排，它可能指向特定的有问题的jar或您拥有的所有库的整体时间安排问题。

使用StdErrLog特定属性启动码头以在两个软件包org.eclipse.jetty.annotations和org.eclipse.jetty.webapp上启用调试的示例。

输出将向您显示JAR文件和每个扫描的jar文件的计时问题。查找“扫描经过的时间”，后缀行将告诉您Web应用程序中每个JAR文件的时间。

$ java -jar ~/code/jetty/distros/jetty-home-9.4.18.v20190429/start.jar -Dorg.eclipse.jetty.annotations.LEVEL=DEBUG -Dorg.eclipse.jetty.webapp.LEVEL=DEBUG
...(snip)...
2019-05-19 11:15:14.796:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/Darwin/libjffi-1.2.jnilib
2019-05-19 11:15:14.796:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/aarch64-Linux/libjffi-1.2.so
2019-05-19 11:15:14.796:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/arm-Linux/libjffi-1.2.so
2019-05-19 11:15:14.797:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/i386-Linux/libjffi-1.2.so
2019-05-19 11:15:14.797:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/i386-SunOS/libjffi-1.2.so
2019-05-19 11:15:14.797:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/i386-Windows/jffi-1.2.dll
2019-05-19 11:15:14.797:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/ppc-AIX/libjffi-1.2.a
2019-05-19 11:15:14.797:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/ppc64-Linux/libjffi-1.2.so
2019-05-19 11:15:14.800:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/ppc64le-Linux/libjffi-1.2.so
2019-05-19 11:15:14.800:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/sparcv9-Linux/libjffi-1.2.so
2019-05-19 11:15:14.800:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/sparcv9-SunOS/libjffi-1.2.so
2019-05-19 11:15:14.800:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/x86_64-FreeBSD/libjffi-1.2.so
2019-05-19 11:15:14.800:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/x86_64-Linux/libjffi-1.2.so
2019-05-19 11:15:14.801:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/x86_64-OpenBSD/libjffi-1.2.so
2019-05-19 11:15:14.801:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/x86_64-SunOS/libjffi-1.2.so
2019-05-19 11:15:14.801:DBUG:oeja.AnnotationParser:qtp1571967156-41: Not a class: jni/x86_64-Windows/jffi-1.2.dll
...(snip)...
2019-05-19 11:15:15.393:INFO:oeja.AnnotationConfiguration:main: Scanning elapsed time=654ms
2019-05-19 11:15:15.393:DBUG:oeja.AnnotationConfiguration:main: Scanned file:///home/joakim/code/jetty/distros/jetty-home-9.4.18.v20190429/lib/servlet-api-3.1.jar in 141ms
2019-05-19 11:15:15.393:DBUG:oeja.AnnotationConfiguration:main: Scanned file:///tmp/jetty-0.0.0.0-8080-demo-with-w3j-libs.war-_demo-with-w3j-libs-any-14235900391383929769.dir/webapp/WEB-INF/classes/ in 1ms
2019-05-19 11:15:15.393:DBUG:oeja.AnnotationConfiguration:main: Scanned file:///tmp/jetty-0.0.0.0-8080-demo-with-w3j-libs.war-_demo-with-w3j-libs-any-14235900391383929769.dir/webapp/WEB-INF/lib/Java-WebSocket-1.3.8.jar in 144ms
2019-05-19 11:15:15.393:DBUG:oeja.AnnotationConfiguration:main: Scanned file:///tmp/jetty-0.0.0.0-8080-demo-with-w3j-libs.war-_demo-with-w3j-libs-any-14235900391383929769.dir/webapp/WEB-INF/lib/abi-4.2.0.jar in 163ms
2019-05-19 11:15:15.393:DBUG:oeja.AnnotationConfiguration:main: Scanned file:///tmp/jetty-0.0.0.0-8080-demo-with-w3j-libs.war-_demo-with-w3j-libs-any-14235900391383929769.dir/webapp/WEB-INF/lib/asm-5.0.3.jar in 126ms
...(snip)...
2019-05-19 11:15:15.394:DBUG:oeja.AnnotationConfiguration:main: Scanned 1 container path jars, 31 WEB-INF/lib jars, 1 WEB-INF/classes dirs in 654ms for context o.e.j.w.WebAppContext@75437611{demo-with-w3j-libs,/demo-with-w3j-libs,file:///tmp/jetty-0.0.0.0-8080-demo-with-w3j-libs.war-_demo-with-w3j-libs-any-14235900391383929769.dir/webapp/,STARTING}{/demo-with-w3j-libs.war}

最后，如果您的计算机速度较慢，并且只想将该超时设置为更大的值，则可以将org.eclipse.jetty.annotations.maxWait值（以秒为单位）设置为更高的值。

可以将其设置为ServletContext属性，Server属性或System属性（按此顺序搜索）。

相关问题
最新问题