Question

我目前正在使用Open Liberty 18.0.0.4及其Microprofile支持。当我尝试构建包含mpHealth-1.0功能的独立可运行Jar时，启动失败并显示

[ERROR   ] CWWKF0033E: The singleton features com.ibm.websphere.appserver.javax.servlet-3.1 and com.ibm.websphere.appserver.javax.servlet-4.0 cannot be loaded at the same time.  The configured features mpHealth-1.0 and jaxrs-2.1 include one or more features that cause the conflict. Your configuration is not supported; update server.xml to remove incompatible features.
[ERROR   ] CWWKF0033E: The singleton features com.ibm.websphere.appserver.javax.annotation-1.2 and com.ibm.websphere.appserver.javax.annotation-1.3 cannot be loaded at the same time.  The configured features mpHealth-1.0 and jaxrs-2.1 include one or more features that cause the conflict. Your configuration is not supported; update server.xml to remove incompatible features.
[ERROR   ] CWWKF0033E: The singleton features com.ibm.websphere.appserver.javaeeCompatible-8.0 and com.ibm.websphere.appserver.javaeeCompatible-7.0 cannot be loaded at the same time.  The configured features jsonb-1.0 and mpHealth-1.0 include one or more features that cause the conflict. Your configuration is not supported; update server.xml to remove incompatible features.
[ERROR   ] CWWKF0033E: The singleton features com.ibm.websphere.appserver.javax.cdi-2.0 and com.ibm.websphere.appserver.javax.cdi-1.2 cannot be loaded at the same time.  The configured features jsonb-1.0 and mpHealth-1.0 include one or more features that cause the conflict. Your configuration is not supported; update server.xml to remove incompatible features.

我正在使用jaxrs-2.1和jsonb-1.0，并且一切正常。添加mpHealth-1.0功能后，我立即收到上述错误。这是server.xml的相关代码段：

    <featureManager>
        <feature>jaxrs-2.1</feature>
        <feature>jsonb-1.0</feature>
        <feature>mpHealth-1.0</feature>
    </featureManager>

这就是开始的Jar在结束时说的（但没有可用的服务）：

[AUDIT   ] CWWKF0012I: The server installed the following features: [jsonb-1.0, servlet-4.0, jndi-1.0, mpHealth-1.0, json-1.0, cdi-1.2, jsonp-1.1, jaxrsClient-2.1, jaxrs-2.1].

Answer 1

之所以会发生此错误，是因为并非所有OpenLiberty功能都相互兼容，并且如果启用了冲突功能，则会出现错误，指出哪些功能发生冲突。应该可以通过在server.xml中启用其他功能来解决该问题，以帮助运行时消除应该启用哪些功能的歧义。

功能冲突的两个主要原因是：

尝试启用同一功能的两个版本（例如foo-1.0和foo-2.0）
启用了Java EE 7和Java EE 8功能的混合（例如EE 7中的cdi-1.2和EE 8中的jaxrs-2.1）

要分解已启用功能的功能依赖性，它看起来像这样：

- jsonb-1.0 -> jsonp-1.1
- jaxrs-2.1 -> cdi-2.0
            -> servlet-4.0
- mpHealth-1.0 -> cdi-1.2 (tolerates cdi-2.0)

看到这些错误的原因是因为OpenLiberty功能管理器没有足够的证据知道它可以故障转移到mpHealth-1.0 -> cdi-2.0依赖项。

要解决此问题，您有两种选择：

在server.xml中启用cdi-2.0功能。这应该有助于消除功能管理器的歧义，以便它可以故障转移到mpHealth-1.0 -> cdi-2.0依赖项。
启用microProfile-2.0便利功能，而不是启用单个功能。在这里，您不必担心功能冲突，但是它将在运行时加载更多功能（例如MP Metrics，MP Config，MP Fault Tolerance等），这将招致一些额外的启动时间和内存占用成本。 li>

包括mpHealth功能可打破Open Liberty中的独立应用程序

1 个答案: