tomcat - 在 Tomcat 7 下启动期间获取完整的 servlet URL

Question

我有一个使用 Tomcat 6 编写的 Web 应用程序，我正在尝试使其与 Tomcat 7 一起使用。在启动期间，应用程序除其他外，还会在某个远程目录中注册其 Web 服务组件。为此，它需要提供自己的 URL。以下(有点天真)方法应该返回 web 服务 URL:

import org.apache.catalina.ServerFactory;
import org.apache.catalina.connector.Connector;
.
.
.
private String getWsUrl(ServletContext context)
            throws UnknownHostException, MalformedURLException {
    String host = java.net.InetAddress.getLocalHost().getCanonicalHostName();
    int port = -1;
    for (Connector c : ServerFactory.getServer().findServices()[0].findConnectors()) {
        if (c.getProtocol().contains("HTTP")) {
            port = c.getPort();
            break;
        }
    }
    URL wsURL = new URL("http", host, port, context.getContextPath()
                + C.WEB_SERVICE_PATH /* this is just a constant string */ );
    return wsURL.toString();
}

ServerFactory.getServer() 部分被证明是有问题的:在 Tomcat 7 中没有 org.apache.catalina.ServerFactory 类。关于如何实现的任何建议为 Tomcat 7 重写这个？我也很乐意拥有更便携、非特定于 tomcat 的代码。

Answer 1

我遇到了同样的问题:我需要知道端口号来为特定的 Tomcat 实例构建 URL，端口号可能会有所不同(因为我运行多个实例进行测试)，并且从 Tomcat 7 开始 ServerFactory 已经消失.

我编写了以下代码来查找和解析 Tomcat server.xml 文件。它解析不多，只是获取 HTTP“端口”和“redirectPort”值。它取决于“catalina.home”或“catalina.base”系统属性，这些属性应该存在于任何正在运行的 Tomcat 实例中。美妙之处在于它不依赖于任何 Tomcat 类，而是使用 JVM 的 XML 解析器。

希望对您有所帮助。

public final class TomcatConfigUtil {

private static final String CONFIG_FILE_PATH = "conf/server.xml";

private static Map<String, String> properties = null;

// No instances, please.
private TomcatConfigUtil() { }


/**
 * Get the configuration as a map of name/value pairs, or throw an exception if it wasn't found.
 * All values are returned as Strings.
 * <ul>
 *   <li> httpPort - the HTTP port</li>
 *   <li> httpRedirectPort - the HTTP redirect port (which seems to be the SSL port) </li>
 * </ul>
 * @exception FileNotFoundException if the configuration file wasn't found
 * @exception IOException if there was a problem reading the configuration file
 * @exception SAXException if there was a problem parsing the configuration file
 */
public static synchronized Map<String, String> getConfig() throws FileNotFoundException, IOException, SAXException {

    if (properties != null) {

        return properties;
    }

    final File serverConfigFile = findServerConfigFile();
    if (serverConfigFile == null) {

        throw new FileNotFoundException("Couldn't find the configuration file.");
    }

    final Map<String, String> tmpProperties = new HashMap<String, String>();

    // Content-handler does the actual parsing.
    final ServerConfigContentHandler contentHandler = new ServerConfigContentHandler(tmpProperties);
    final XMLReader xmlReader = XMLReaderFactory.createXMLReader();
    xmlReader.setContentHandler(contentHandler);

    // Pass the config file as the input source for parsing.
    final FileReader fileReader = new FileReader(serverConfigFile);
    xmlReader.parse(new InputSource(fileReader));
    fileReader.close();

    return (properties = Collections.unmodifiableMap(tmpProperties));
}


private static File findServerConfigFile() {

    if (System.getProperty("catalina.home") != null) {

        final File file = new File(System.getProperty("catalina.home"), CONFIG_FILE_PATH);
        if (file.isFile()) {

            return file;
        }
    }

    if (System.getProperty("catalina.base") != null) {

        final File file = new File(System.getProperty("catalina.base"), CONFIG_FILE_PATH);
        if (file.isFile()) {

            return file;
        }
    }

    return null;
}


/**
 * ContentHandler implementation for the XML parser.
 */
private static class ServerConfigContentHandler implements ContentHandler {

    private final Map<String, String> map;
    private boolean inServerElement;
    private boolean inCatalinaServiceElement;


    private ServerConfigContentHandler(final Map<String, String> map) {

        this.map = map;
    }

    @Override
    public void startDocument() throws SAXException {

        this.inServerElement = false;
        this.inCatalinaServiceElement = false;
    }

    @Override
    public void startElement(final String uri, final String localName, final String qName, final Attributes atts) throws SAXException {

        if (!this.inServerElement && "Server".equals(localName)) {

            this.inServerElement = true;
        }
        else if (this.inServerElement && "Service".equals(localName) && "Catalina".equals(atts.getValue("name"))) {

            this.inCatalinaServiceElement = true;
        }
        else if (this.inCatalinaServiceElement && "Connector".equals(localName) && "HTTP/1.1".equals(atts.getValue("protocol"))) {

            if ((atts.getValue("SSLEnabled") == null || "false".equals(atts.getValue("SSLEnabled"))) &&
                    (atts.getValue("secure") == null || "false".equals(atts.getValue("secure"))) &&
                    (atts.getValue("scheme") == null || "http".equals(atts.getValue("scheme")))) {

                        final String portStr = atts.getValue("port");
                        if (portStr != null) {

                            this.map.put("httpPort", portStr);
                        }
                        final String redirectPortStr = atts.getValue("redirectPort");
                        if (redirectPortStr != null) {

                            this.map.put("httpRedirectPort", redirectPortStr);
                        }
                    }
        }
    }

    @Override
    public void endElement(final String uri, final String localName, final String qName) throws SAXException {

        if (this.inCatalinaServiceElement && "Service".equals(localName)) {

            this.inCatalinaServiceElement = false;
        }
        else if (this.inServerElement && "Server".equals(localName)) {

            this.inServerElement = false;
        }
    }

    @Override
    public void endDocument() throws SAXException {

        this.inServerElement = false;
        this.inCatalinaServiceElement = false;
    }

    @Override
    public void characters(final char[] ch, final int start, final int length) throws SAXException { }

    @Override
    public void endPrefixMapping(final String prefix) throws SAXException { }

    @Override
    public void ignorableWhitespace(final char[] ch, final int start, final int length) throws SAXException { }

    @Override
    public void processingInstruction(final String target, final String data) throws SAXException { }

    @Override
    public void setDocumentLocator(final Locator locator) { }

    @Override
    public void skippedEntity(final String name) throws SAXException { }

    @Override
    public void startPrefixMapping(final String prefix, final String uri) throws SAXException { }
}