本人有一段时间没有接触企业搜索引擎之连接器的开发了，连接器是涉及企业搜索引擎一个重要的组件，在数据源与企业搜索引擎中间起一个桥梁的作用，类似于数据库之JDBC，通过连接器将不同数据源的数据适配到企业搜索引擎系统
本文将描述怎样构建连接器应用实例，并开发一个简单的客户端进行测试
我们先用myeclipse建立一个web应用，命名为connector-manager，并添加相关依赖，包括连接器的相关jar依赖
本人当前引入http连接器和db连接器，还可以包括更多的连接器类型，比如数据仓库、共享文件系统、企业邮件等
pom.xml文件如下：
<dependencies> <dependency> <groupId>com.google.enterprise.connector</groupId> <artifactId>connector</artifactId> <version>3.0.8</version> </dependency> <dependency> <groupId>com.google.enterprise.connector</groupId> <artifactId>connector-http</artifactId> <version>2.0M3</version> </dependency> <dependency> <groupId>com.google.enterprise.connector</groupId> <artifactId>connector-db</artifactId> <version>3.0.0</version> </dependency> </dependencies>
然后在myeclipse里面将该web应用编译并添加到tomcat服务器，运行tomcat
我们这时在浏览器打开http://localhost:8080/connector-manager/就可以看到如下显示：
连接器提供了一系列的servlet供客户端以编程方式调用，从而实现对连接器的管理（请求这些servlet有ge方式和post方式），我们来测试查看连接器提供了哪些数据源连接类型，servlet请求相对路径为/getConnectorList，在浏览器打开http://localhost:8080/connector-manager/getConnectorList
上面可以看到，目前提供了数据库连接类型和http连接类型
如果我们要建立一个连接实例，则需要通过post方式请求相关servlet，首先需要获取需要提交哪些post参数，可以通过相对路径为/getConfigForm的servlet获取，在浏览器打开http://localhost:8080/connector-manager/getConfigForm?ConnectorType=DBConnector可以获取到数据库连接实例的post参数（如果是http连接器，则将参数修改为ConnectorType=http-connector）
上面只是简单的通过浏览器来请求连接器的servlet，更丰富的功能则需要以编程方式来请求这些servlet，从而实现连接器的管理
接下来本人在eclipse建立一个java project，命名为SerchEngine，在pom.xml文件添加相关依赖
<dependencies> <!-- httpclient --> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient</artifactId> <version>4.2.3</version> </dependency> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpmime</artifactId> <version>4.2.3</version> </dependency> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient-cache</artifactId> <version>4.2.3</version> </dependency> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>fluent-hc</artifactId> <version>4.2.3</version> </dependency> <dependency> <groupId>dom4j</groupId> <artifactId>dom4j</artifactId> <version>1.6.1</version> </dependency> </dependencies>
本人这里的servlet请求是通过httpclient组件实现的，所以添加了httpclient组件的相关依赖；然后提交的xml数据和返回的xml数据都是通过dom4j来解析的，所以同时添加了dom4j的相关依赖
为了实现方法的公用，本人这里建立一个servlet请求类ConnectorManagerRequestUtils，包括get方式与 post方式的请求，完整代码如下：
public class ConnectorManagerRequestUtils { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub ConnectorManager connectorManager=new ConnectorManager(); connectorManager.setUrl("http://localhost:8080/connector-manager"); Map<String, String> paramsMap=new HashMap<String, String>(); paramsMap.put("ConnectorType", "DBConnector"); Element element=ConnectorManagerRequestUtils.sendGet(connectorManager, "/getConfigForm", paramsMap); //Element element=ConnectorManagerRequestUtils.sendGet(connectorManager, "/getConnectorList", paramsMap); System.out.println(element.asXML()); } private static final Logger LOGGER = Logger.getLogger(ConnectorManagerRequestUtils.class.getName()); public static Element sendGet(ConnectorManager connectorManager, String servletPath, Map<String, String> paramsMap) { if (paramsMap == null) { paramsMap = new HashMap<String, String>(); } try { HttpParams params = new BasicHttpParams(); for (Iterator<String> it = paramsMap.keySet().iterator(); it.hasNext();) { String paramName = (String) it.next(); String paramValue = (String) paramsMap.get(paramName); params.setParameter(paramName, paramValue); } HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1); HttpProtocolParams.setContentCharset(params, "UTF-8"); HttpProtocolParams.setUserAgent(params, "HttpComponents/1.1"); HttpProtocolParams.setUseExpectContinue(params, true); BasicHttpProcessor httpproc = new BasicHttpProcessor(); // Required protocol interceptors httpproc.addInterceptor(new RequestContent()); httpproc.addInterceptor(new RequestTargetHost()); // Recommended protocol interceptors httpproc.addInterceptor(new RequestConnControl()); httpproc.addInterceptor(new RequestUserAgent()); httpproc.addInterceptor(new RequestExpectContinue()); HttpRequestExecutor httpexecutor = new HttpRequestExecutor(); HttpContext context = new BasicHttpContext(null); URL connectorManagerURL = new URL(connectorManager.getUrl()); HttpHost host = new HttpHost(connectorManagerURL.getHost(), connectorManagerURL.getPort()); DefaultHttpClientConnection conn = new DefaultHttpClientConnection(); ConnectionReuseStrategy connStrategy = new DefaultConnectionReuseStrategy(); context.setAttribute(ExecutionContext.HTTP_CONNECTION, conn); context.setAttribute(ExecutionContext.HTTP_TARGET_HOST, host); try { String target = connectorManager.getUrl() + servletPath; boolean firstParam = true; for (Iterator<String> it = paramsMap.keySet().iterator(); it.hasNext();) { String paramName = (String) it.next(); String paramValue = (String) paramsMap.get(paramName); if (firstParam) { target += "?"; firstParam = false; } else { target += "&"; } target += paramName + "=" + paramValue; } if (!conn.isOpen()) { Socket socket = new Socket(host.getHostName(), host.getPort()); conn.bind(socket, params); } BasicHttpEntityEnclosingRequest request = new BasicHttpEntityEnclosingRequest("GET", target); LOGGER.fine(">> Request URI: " + request.getRequestLine().getUri()); request.setParams(params); httpexecutor.preProcess(request, httpproc, context); HttpResponse response = httpexecutor.execute(request, conn, context); response.setParams(params); httpexecutor.postProcess(response, httpproc, context); LOGGER.fine("<< Response: " + response.getStatusLine()); String entityText = EntityUtils.toString(response.getEntity()); LOGGER.fine(entityText); LOGGER.fine("=============="); if (!connStrategy.keepAlive(response, context)) { conn.close(); } else { LOGGER.fine("Connection kept alive..."); } try { Document xml = DocumentHelper.parseText(entityText); return xml.getRootElement(); } catch (Exception e) { LOGGER.severe("Error caused by text : " + entityText); throw e; } } finally { conn.close(); } } catch (Exception e) { throw new RuntimeException(e); } } public static Element sendPost(ConnectorManager connectorManager, String servletPath, Document document) { try { HttpParams params = new BasicHttpParams(); HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1); HttpProtocolParams.setContentCharset(params, "UTF-8"); HttpProtocolParams.setUserAgent(params, "HttpComponents/1.1"); HttpProtocolParams.setUseExpectContinue(params, true); BasicHttpProcessor httpproc = new BasicHttpProcessor(); // Required protocol interceptors httpproc.addInterceptor(new RequestContent()); httpproc.addInterceptor(new RequestTargetHost()); // Recommended protocol interceptors httpproc.addInterceptor(new RequestConnControl()); httpproc.addInterceptor(new RequestUserAgent()); httpproc.addInterceptor(new RequestExpectContinue()); HttpRequestExecutor httpexecutor = new HttpRequestExecutor(); HttpContext context = new BasicHttpContext(null); URL connectorManagerURL = new URL(connectorManager.getUrl()); HttpHost host = new HttpHost(connectorManagerURL.getHost(), connectorManagerURL.getPort()); DefaultHttpClientConnection conn = new DefaultHttpClientConnection(); ConnectionReuseStrategy connStrategy = new DefaultConnectionReuseStrategy(); context.setAttribute(ExecutionContext.HTTP_CONNECTION, conn); context.setAttribute(ExecutionContext.HTTP_TARGET_HOST, host); try { HttpEntity requestBody; if (document != null) { // OutputFormat format = OutputFormat.createPrettyPrint(); OutputFormat format = OutputFormat.createCompactFormat(); StringWriter stringWriter = new StringWriter(); XMLWriter xmlWriter = new XMLWriter(stringWriter, format); xmlWriter.write(document); String xmlAsString = stringWriter.toString(); requestBody = new StringEntity(xmlAsString, "UTF-8"); } else { requestBody = null; } if (!conn.isOpen()) { Socket socket = new Socket(host.getHostName(), host.getPort()); conn.bind(socket, params); } String target = connectorManager.getUrl() + servletPath; BasicHttpEntityEnclosingRequest request = new BasicHttpEntityEnclosingRequest("POST", target); request.setEntity(requestBody); LOGGER.info(">> Request URI: " + request.getRequestLine().getUri()); request.setParams(params); httpexecutor.preProcess(request, httpproc, context); HttpResponse response = httpexecutor.execute(request, conn, context); response.setParams(params); httpexecutor.postProcess(response, httpproc, context); LOGGER.info("<< Response: " + response.getStatusLine()); String entityText = EntityUtils.toString(response.getEntity()); LOGGER.info(entityText); LOGGER.info("=============="); if (!connStrategy.keepAlive(response, context)) { conn.close(); } else { LOGGER.info("Connection kept alive..."); } Document xml = DocumentHelper.parseText(entityText); return xml.getRootElement(); } finally { conn.close(); } } catch (Exception e) { throw new RuntimeException(e); } } }
现在运行该类的main方法，是不是在控制台看到和上面浏览器方式相同的输出呢？
更丰富的功能待后文接着分析，本文先到这里
---------------------------------------------------------------------------
本系列企业搜索引擎开发之连接器connector系本人原创
转载请注明出处 博客园 刺猬的温驯
本人邮箱： chenying998179@163#com （#改为.）