FGDCChecker

FGDC介绍

FGDC,即美国联邦地理数据委员会（FederalGeodata Commission），其提供了服务状态检查器（Service Status Checker ，SSC）来验证、测试和评分地理空间 Web 服务。

在这里，我们使用liveTest API来测试我们监测的服务状态，作为综合评分的参考。

Supported API Method: GET
Request Format: https://statuschecker.fgdc.gov/api/v2/liveTest?auth=&type=&url=&[other = pairs]

结果解析

设置返回格式为XML，使用jdom2进行解析，在pom.xml中引入依赖：

<dependency>
    <groupId>org.jdom</groupId>
    <artifactId>jdom2</artifactId>
    <version>2.0.6</version>
</dependency>

JDOM操作xml常用类

Document：表示整个xml文档，是一个树形结构
Eelment：表示一个xml的元素，提供方法操作其子元素，如文本，属性和名称空间等
Attribute：表示元素包含的属性
Text：表示xml文本信息
XMLOutputter：xml输出流，底层是通过JDK中流实现
Format：提供xml文件输出的编码、样式和排版等设置

一个示例返回文档如下：

可以发现，我们关心的属性位于response/service/summary/scoredTest/performance下，相应的解析代码如下：

SAXBuilder parser = new SAXBuilder();
Document FGDCDoc = parser.build(FGDCRequestURL);
Element RootEle = FGDCDoc.getRootElement();
Element Service = RootEle.getChild("service", RootEle.getNamespace());
Element summary = Service.getChild("summary", RootEle.getNamespace());
Element scoredTest = summary.getChild("scoredTest", RootEle.getNamespace());
List<Element> performance = scoredTest.getChildren("performance", RootEle.getNamespace());
fp.setFGDC_time(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(Calendar.getInstance().getTime()));
Element currentScore = performance.get(1);
String scoreString = currentScore.getValue();
fp.setFGDC_score(Float.parseFloat(scoreString));
Element currentSpeed = performance.get(0);
String currentSpeedString = currentSpeed.getValue();
fp.setFGDC_speed(Float.parseFloat(currentSpeedString));

其中，FGDC_score为FGDC基于web服务速度性能和响应正确性所给出的综合打分（百分制），FGDC_speed为测试所用耗时（秒）

同时，FGDC还进行了一系列测试，将测试成功与否存于路径response/service/test下，解析代码如下：

//<!-- 0 = Failed, 1 = Success, 2 = IP banned - Not tested and -99.99 = Not tested -->
List<Element> testList = Service.getChildren("test", RootEle.getNamespace());
for (Element element : testList) {
    if (element.getAttributeValue("type").compareTo("httpServer") == 0) {
        Element output = element.getChild("output", RootEle.getNamespace());
        fp.setHttpServerSuccess(Float.parseFloat(output.getValue()));
    }
    else if (element.getAttributeValue("type").compareTo("getCapabilities") == 0) {
        Element output = element.getChild("output", RootEle.getNamespace());
        fp.setGetCapabilitiesSuccess(Float.parseFloat(output.getValue()));
    }
    else if (element.getAttributeValue("type").compareTo("generatedGetCapabilities") == 0) {
        Element output = element.getChild("output", RootEle.getNamespace());
        fp.setGeneratedGetCapabilitiesSuccess(Float.parseFloat(output.getValue()));
    }
    else if (element.getAttributeValue("type").compareTo("getMap") == 0) {
        Element output = element.getChild("output", RootEle.getNamespace());
        fp.setGetMapSuccess(Float.parseFloat(output.getValue()));
    }
}

详细代码

FGDCChecker.java

@NoArgsConstructor
@AllArgsConstructor
public class FGDCChecker {
    private String URL;

    public FGDCPerformance GetFGDCPerformance(){
        FGDCPerformance fp = new FGDCPerformance();
        String FGDCRequestURL = "https://statuschecker.fgdc.gov/api/v2/liveTest?auth={yourKey}&type=WMS&url=" + this.URL  + "&formattype=XML";
        try {
            SAXBuilder parser = new SAXBuilder();
            Document FGDCDoc = parser.build(FGDCRequestURL);
            Element RootEle = FGDCDoc.getRootElement();
            Element Service = RootEle.getChild("service", RootEle.getNamespace());
            Element summary = Service.getChild("summary", RootEle.getNamespace());
            Element scoredTest = summary.getChild("scoredTest", RootEle.getNamespace());
            List<Element> performance = scoredTest.getChildren("performance", RootEle.getNamespace());

            fp.setFGDC_time(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(Calendar.getInstance().getTime()));

            Element currentScore = performance.get(1);
            String scoreString = currentScore.getValue();
            fp.setFGDC_score(Float.parseFloat(scoreString));

            Element currentSpeed = performance.get(0);
            String currentSpeedString = currentSpeed.getValue();
            fp.setFGDC_speed(Float.parseFloat(currentSpeedString));

//            <!-- 0 = Failed, 1 = Success, 2 = IP banned - Not tested and -99.99 = Not tested -->
            List<Element> testList = Service.getChildren("test", RootEle.getNamespace());
            for (Element element : testList) {
                if (element.getAttributeValue("type").compareTo("httpServer") == 0) {
                    Element output = element.getChild("output", RootEle.getNamespace());
                    fp.setHttpServerSuccess(Float.parseFloat(output.getValue()));
                }
                else if (element.getAttributeValue("type").compareTo("getCapabilities") == 0) {
                    Element output = element.getChild("output", RootEle.getNamespace());
                    fp.setGetCapabilitiesSuccess(Float.parseFloat(output.getValue()));
                }
                else if (element.getAttributeValue("type").compareTo("generatedGetCapabilities") == 0) {
                    Element output = element.getChild("output", RootEle.getNamespace());
                    fp.setGeneratedGetCapabilitiesSuccess(Float.parseFloat(output.getValue()));
                }
                else if (element.getAttributeValue("type").compareTo("getMap") == 0) {
                    Element output = element.getChild("output", RootEle.getNamespace());
                    fp.setGetMapSuccess(Float.parseFloat(output.getValue()));
                }
            }
            return fp;
        } catch (Exception e) {
            fp.setFGDC_time(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(Calendar.getInstance().getTime()));
            fp.setFGDC_score(-1);
            fp.setFGDC_speed(-1);
            fp.setHttpServerSuccess(-1);
            fp.setGetCapabilitiesSuccess(-1);
            fp.setGeneratedGetCapabilitiesSuccess(-1);
            fp.setGetMapSuccess(-1);
            return fp;
        }
    }
}