文件中的log4j2配置

Question

我正在使用log4j的现有系统上工作，我想更新到log4j2。

有一个自定义Springbean从文件加载配置。我需要保持这种方法。我不能使用"log4j.configuration文件"系统属性。

我们有一个属性文件，其中指定了当前log4j.xml的路径（NFS共享）

Springbean有以下代码。。。

public class Log4jConfigurationBean implements ResourceLoaderAware,
    InitializingBean {

private ResourceLoader resourceLoader;

private boolean enabled;

private String location;

/**
 * Default, no argument constructor.
 */
public Log4jConfigurationBean() {
    enabled = true;
}

/**
 * Sets whether or not this bean should load an external configuration
 * defined by {@link #setLocation(Resource)}. If <code>false</code>, this
 * bean does nothing.
 * 
 * <p>
 * Default value is <code>true</code>.
 * </p>
 * 
 * @param enabled
 *            <code>false</code> causes this bean to do nothing
 */
public void setEnabled(final boolean enabled) {
    this.enabled = enabled;
}

/**
 * Sets the location of the external log4j configuration (xml or properties)
 * to be loaded.
 * 
 * @param location
 *            the location of the external configuration to be loaded.
 * @throws IllegalStateException
 *             if there is a problem resolving the location resource
 * @throws NullPointerException
 *             if <code>resource</code> is <code>null</code>
 */
public void setLocation(final String location) {
    this.location = StringUtils.trimToNull(location);
}

@Override
public void setResourceLoader(final ResourceLoader resourceLoader) {
    this.resourceLoader = resourceLoader;
}

/**
 * @throws IllegalStateException
 *             if enabled and no location has be set, or if the external
 *             configuration is neither xml or properties.
 */
@Override
public void afterPropertiesSet() throws Exception {
    URL configURL = null;
    if (null != location) {
        try {
            final Resource resource = resourceLoader.getResource(location);
            if (null != resource) {
                configURL = resource.getURL();
            }
        } catch (IOException e) {
            throw new IllegalArgumentException(
                    "Could not resolve configuration location due to error: ",
                    e);
        }
    }
    if (enabled && null == configURL) {
        throw new IllegalStateException(
                "Log4j configuration enabled, but configuration location is not set.");
    }
    if (enabled) {
        if (configURL.getFile().toLowerCase().endsWith(".xml")) {
            DOMConfigurator.configure(configURL);
        } else if (configURL.getFile().toLowerCase()
                .endsWith(".properties")) {
            PropertyConfigurator.configure(configURL);
        } else {
            throw new IllegalStateException(
                    "Configuration must be properties or xml: "
                            + configURL.getFile());
        }
    }
}

}

在log4j2中，没有PropertyConfiguration。如何加载log4j2。xml文件也是这样。

log4j2.xml文件的文件路径在Spring属性文件中指定。

目标是让war文件在类路径中包含一个log4j2.xml文件。这将在您的本地框上开发时使用。

当Web应用部署到qa环境时，会有一个属性文件，其中包含以下键/值对...

# Should an external file be used for log4j configuration
log4j.enabled=true
log4j.location=file:/paht to log4j2.xml

Springbean正在使用这些值来确定是否存在外部log4j2。应该使用xml文件，而不是类路径上的文件。

我尝试了这样的Springbean...代码被执行，但它仍然使用类路径上的配置文件。

public class Log4j2ConfigurationBean implements ResourceLoaderAware, InitializingBean {
private static final Logger log = LoggerFactory.getLogger(Log4j2ConfigurationBean.class);
private ResourceLoader resourceLoader;
private boolean enabled;
private String location;

/**
 * Default, no argument constructor.
 */
public Log4j2ConfigurationBean() {
    enabled = true;
}

/**
 * Sets whether or not this bean should load an external configuration defined by {@link #setLocation(Resource)}. If <code>false</code>, this bean does nothing.
 * 
 * <p>
 * Default value is <code>true</code>.
 * </p>
 * 
 * @param enabled
 *            <code>false</code> causes this bean to do nothing
 */
public void setEnabled(final boolean enabled) {
    this.enabled = enabled;
}

/**
 * Sets the location of the external log4j configuration (xml or properties) to be loaded.
 * 
 * @param location
 *            the location of the external configuration to be loaded.
 * @throws IllegalStateException
 *             if there is a problem resolving the location resource
 * @throws NullPointerException
 *             if <code>resource</code> is <code>null</code>
 */
public void setLocation(final String location) {
    this.location = StringUtils.trimToNull(location);
}

@Override
public void setResourceLoader(final ResourceLoader resourceLoader) {
    this.resourceLoader = resourceLoader;
}

/**
 * @throws IllegalStateException
 *             if enabled and no location has be set, or if the external configuration is neither xml or properties.
 */
@Override
public void afterPropertiesSet() throws Exception {
    URL configURL = null;
    if (enabled) {
        if (StringUtils.isBlank(location)) {
            throw new IllegalStateException("Log4j2 configuration enabled, but configuration location is not set.");
        }
        try {
            System.out.println(this.getClass().getName() + " : Loading log4j2 configuration with " + location);
            final Resource resource = resourceLoader.getResource(location);
            if (null != resource) {
                configURL = resource.getURL();
            }
        } catch (IOException e) {
            throw new IllegalArgumentException("Could not resolve configuration location due to error: ", e);
        }
        if (configURL.getFile().toLowerCase().endsWith(".xml")) {
            try {
                System.setProperty("Log4jContextSelector", "org.apache.logging.log4j.core.async.AsyncLoggerContextSelector");
                System.setProperty("AsyncLogger.RingBufferSize", "8192");
                ConfigurationFactory configurationFactory = XmlConfigurationFactory.getInstance();
                ConfigurationSource configurationSource = new ConfigurationSource(configURL.openStream(), configURL);
                Configuration configuration = configurationFactory.getConfiguration(configurationSource);
                configuration.start();
                log.info("Log4j2 configured with {}", location);
                log.info("System property Log4jContextSelector set to {}", System.getProperty("Log4jContextSelector"));
                log.info("System property AsyncLogger.RingBufferSize set to {}", System.getProperty("AsyncLogger.RingBufferSize"));
            } catch (Exception e) {
                System.out.println(this.getClass().getName() + " : Could not initialize log4j2 with resource " + location);
                System.out.println(e.getStackTrace());
            }
        } else {
            throw new IllegalStateException("Configuration must be xml: " + configURL.getFile());
        }
    } else {
        System.out.println(this.getClass().getName() + " : External log4j2 configuration not configured.");
    }
}

}

谢谢

Answer 1

查看如何在没有配置文件的代码中配置log4j2？本节-http://logging.apache.org/log4j/2.x/faq.html