编写轻量级WebService服务器

标题：编写轻量级WebService服务器
作者：Lee353086(kagula)
日期：2007-12-15

目的：通过示例代码和其它样例文件，你将了解[1]如何解析和生成soap信息[2]简单的http server端编程

阅读对象：
java程序员

环境：
[1]IBM JAVA JDK(From WebSphere6.1安装包)
[2]MyEclipse5.1.x

内容：
java源代码(含大量注解)和xml样例文件。

注意：
NHttpServer.java文件，根据
http://svn.apache.org/repos/asf/jakarta/httpcomponents/httpcore/tags/4.0-alpha6/module-nio/src/examples/org/apache/http/examples/nio/NHttpServer.java
文件修改而来。

必须信赖包：
[1]saaj.jar（可以使用Axis1.4发行包中的saaj.jar）
[2]httpcore-4.0-alpha6.jar、httpcore-nio-4.0-alpha6.jar等包来自http://jakarta.apache.org/httpcomponents/

正文：
第一部份：NHttpServer.java源文件清单
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import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.InetSocketAddress;
import java.net.URLDecoder;
import java.util.Iterator;

import javax.xml.soap.MessageFactory;
import javax.xml.soap.Name;
import javax.xml.soap.SOAPBody;
import javax.xml.soap.SOAPBodyElement;
import javax.xml.soap.SOAPElement;
import javax.xml.soap.SOAPEnvelope;
import javax.xml.soap.SOAPMessage;
import javax.xml.soap.SOAPPart;
import javax.xml.transform.stream.StreamSource;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.http.HttpEntity;
import org.apache.http.HttpEntityEnclosingRequest;
import org.apache.http.HttpException;
import org.apache.http.HttpRequest;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.MethodNotSupportedException;
import org.apache.http.entity.ContentProducer;
import org.apache.http.entity.EntityTemplate;
import org.apache.http.entity.FileEntity;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.DefaultConnectionReuseStrategy;
import org.apache.http.impl.DefaultHttpResponseFactory;
import org.apache.http.impl.nio.DefaultServerIOEventDispatch;
import org.apache.http.impl.nio.reactor.DefaultListeningIOReactor;
import org.apache.http.nio.NHttpConnection;
import org.apache.http.nio.protocol.BufferingHttpServiceHandler;
import org.apache.http.nio.protocol.EventListener;
import org.apache.http.nio.reactor.IOEventDispatch;
import org.apache.http.nio.reactor.ListeningIOReactor;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.CoreConnectionPNames;
import org.apache.http.params.CoreProtocolPNames;
import org.apache.http.params.HttpParams;
import org.apache.http.protocol.BasicHttpProcessor;
import org.apache.http.protocol.HttpContext;
import org.apache.http.protocol.HttpRequestHandler;
import org.apache.http.protocol.HttpRequestHandlerRegistry;
import org.apache.http.protocol.ResponseConnControl;
import org.apache.http.protocol.ResponseContent;
import org.apache.http.protocol.ResponseDate;
import org.apache.http.protocol.ResponseServer;
import org.apache.http.util.EntityUtils;

public class NHttpServer {

public static void main(String[] args) throws Exception {
Log log=LogFactory.getLog("NHttpServer");

//设置Http服务器根目录.begin
args=new String[1];
args[0]="WebRoot";
// 设置Http服务器根目录.end

if (args.length < 1) {
log.error("Please specify document root directory");
System.exit(1);
}

/**
* 设置Http Server参数
*/
HttpParams params = new BasicHttpParams(null);
params
.setIntParameter(CoreConnectionPNames.SO_TIMEOUT, 30*60*1000)
.setIntParameter(CoreConnectionPNames.SOCKET_BUFFER_SIZE, 8 * 1024)
.setBooleanParameter(CoreConnectionPNames.STALE_CONNECTION_CHECK, false)
.setBooleanParameter(CoreConnectionPNames.TCP_NODELAY, true)
.setParameter(CoreProtocolPNames.ORIGIN_SERVER, "Jakarta-HttpComponents-NIO/1.1");

/**
* Httpproc拦截器
*/
BasicHttpProcessor httpproc = new BasicHttpProcessor();
httpproc.addInterceptor(new ResponseDate());
httpproc.addInterceptor(new ResponseServer());
httpproc.addInterceptor(new ResponseContent());
httpproc.addInterceptor(new ResponseConnControl());

BufferingHttpServiceHandler handler = new BufferingHttpServiceHandler(
httpproc,
new DefaultHttpResponseFactory(),
new DefaultConnectionReuseStrategy(),
params);

// Set up request handlers
HttpRequestHandlerRegistry reqistry = new HttpRequestHandlerRegistry();
reqistry.register("*", new HttpFileHandler(args[0]));

handler.setHandlerResolver(reqistry);

// Provide an event logger
handler.setEventListener(new EventLogger());

IOEventDispatch ioEventDispatch = new DefaultServerIOEventDispatch(handler, params);
ListeningIOReactor ioReactor = new DefaultListeningIOReactor(2, params);
try {
ioReactor.listen(new InetSocketAddress(8080));
ioReactor.execute(ioEventDispatch);
} catch (InterruptedIOException ex) {
log.error("Interrupted");
} catch (IOException e) {
log.error("I/O error: " + e.getMessage());
}
log.debug("Shutdown");
}

static class HttpFileHandler implements HttpRequestHandler {

private final String docRoot;
private final Log log=LogFactory.getLog("HttpFileHandler");

public HttpFileHandler(final String docRoot) {
super();
this.docRoot = docRoot;
}

public void handle(
final HttpRequest request,
final HttpResponse response,
final HttpContext context) throws HttpException, IOException {

String method = request.getRequestLine().getMethod().toUpperCase();
log.debug("request.getRequestLine().getMethod().toUpperCase() => "+method);

if (!method.equals("GET") && !method.equals("HEAD") && !method.equals("POST")) {
throw new MethodNotSupportedException(method + " method not supported");
}

//测试SOAP原始上传内容.begin
/*
if (request instanceof HttpEntityEnclosingRequest) {
HttpEntity entity = ((HttpEntityEnclosingRequest) request).getEntity();
byte[] entityContent = EntityUtils.toByteArray(entity);
log.debug("Incoming entity content (bytes): " + entityContent.length);
log.debug("Incoming entity content (String):"+new String(entityContent,"utf-8"));
}
*/
//测试SOAP原始上传内容.end

//检查上传url（不包括本地服务器地址）.begin
String target = request.getRequestLine().getUri();
log.debug("request.getRequestLine().getUri() => "+target);
// 检查上传url（不包括本地服务器地址）.end

String strWS="/ws";
if(target.equalsIgnoreCase(strWS))
{
log.debug("处理WebService服务请求");
wsProcessing(request,response);
}else {
//默认,http请求,处理函数
final File file = new File(this.docRoot, URLDecoder.decode(target, "UTF-8"));
defaultProcessing(response,file);
}

}

/**
* WebService请求，处理函数
*
*/
public void wsProcessing(final HttpRequest request,final HttpResponse response)
{
if (request instanceof HttpEntityEnclosingRequest) {
try {
//取从Axis1.4发过来的请求
HttpEntity entity = ((HttpEntityEnclosingRequest) request).getEntity();
byte[] entityContent = EntityUtils.toByteArray(entity);

// create the actual message
MessageFactory messageFactory = MessageFactory.newInstance();
SOAPMessage message = messageFactory.createMessage();

//Create objects for the message parts
SOAPPart soapPart = message.getSOAPPart();

//construct from ByteArrayInputStream
StreamSource preppedMsgSrc = new StreamSource(new ByteArrayInputStream(entityContent));
/*
String MsgSrc=new String("<soapenv:Envelope xmlns:soapenv=/"http://schemas.xmlsoap.org/soap/envelope//" xmlns:xsd=/"http://www.w3.org/2001/XMLSchema/" xmlns:xsi=/"http://www.w3.org/2001/XMLSchema-instance/"><soapenv:Body><JWSendLog soapenv:encodingStyle=/"http://schemas.xmlsoap.org/soap/encoding//"><arg0 xsi:type=/"soapenc:string/" xmlns:soapenc=/"http://schemas.xmlsoap.org/soap/encoding//">cd8f0a5a585940aa8420fb439311656d</arg0><arg1 xsi:type=/"soapenc:string/" xmlns:soapenc=/"http://schemas.xmlsoap.org/soap/encoding//">0</arg1><arg2 xsi:type=/"soapenc:string/" xmlns:soapenc=/"http://schemas.xmlsoap.org/soap/encoding//">kagula uid</arg2></JWSendLog></soapenv:Body></soapenv:Envelope>");
StreamSource preppedMsgSrc = new StreamSource(new ByteArrayInputStream(MsgSrc.getBytes()));
*/
soapPart.setContent(preppedMsgSrc);

//Save the message
// message.saveChanges();

//iterator body content.begin
SOAPEnvelope envelope = soapPart.getEnvelope();
SOAPBody body=envelope.getBody();
Iterator iter=body.getChildElements();
while(iter.hasNext())
{
//may be could be for getting call method name
//among these important is getNodeName()，getValue()
//SOAPElement content.begin
SOAPElement element=(SOAPElement)iter.next();
log.debug("SOAPElement.getNodeName="+element.getNodeName()+",getNodeType="+element.getNodeType()+",getNodeValue="+element.getNodeValue());
log.debug("SOAPElement.getPrefix="+element.getPrefix()+",getTagName="+element.getTagName()+",getValue="+element.getValue());
//SOAPElement content.end

Iterator eiter=element.getChildElements();
while(eiter.hasNext())
{
//may be could read for getting call method 's parameters
//SOAPElement content.begin
SOAPElement subelement=(SOAPElement)eiter.next();
log.debug("SOAPElement.getNodeName="+subelement.getNodeName()+",getNodeType="+subelement.getNodeType()+",getNodeValue="+subelement.getNodeValue());
log.debug("SOAPElement.getPrefix="+subelement.getPrefix()+",getTagName="+subelement.getTagName()+",getValue="+subelement.getValue());
//SOAPElement content.end
}
}
//iterator body content.end

//Check the input
/*
System.out.println("/nREQUEST:/n");
message.writeTo(System.out);
System.out.println();
*/
}catch(Exception e)
{
log.error("soap error:"+e.toString());
}
}//end if (request instanceof HttpEntityEnclosingRequest)

//返回SOAP格式，信息
returnSOAP(response,new String("你好！这是我的反馈信息。(Hello!It's my response msg.)"));
}

/**
* 返回WebService服务请求的响应
* @param response
* @param strMsg
*/
public void returnSOAP(final HttpResponse response,final String strMsg)
{
try {
MessageFactory fac = MessageFactory.newInstance();
SOAPMessage msg=fac.createMessage();
SOAPPart part=msg.getSOAPPart();
SOAPEnvelope envelope=part.getEnvelope();
SOAPBody body=envelope.getBody();
Name bodyName=envelope.createName("Response", "", "http://tempuri.org/");
SOAPBodyElement list =body.addBodyElement(bodyName);

Name resultN = envelope.createName("result");
SOAPElement result = list.addChildElement(resultN);
result.addTextNode(strMsg);

msg.saveChanges();

msg.writeTo(System.out);
log.debug("SOAPEnvelope.toString()"+envelope.toString());

//response
response.setStatusCode(HttpStatus.SC_OK);
StringEntity entity=new StringEntity(envelope.toString());
response.setEntity(entity);

} catch (Exception ex) {
log.error("returnSOPA()=>"+ex.toString());
}
}

/**
* http请求，缺省处理函数
* @param response
* @param file
*/
public void defaultProcessing(final HttpResponse response,final File file)
{
if (!file.exists()) {

response.setStatusCode(HttpStatus.SC_NOT_FOUND);
EntityTemplate body = new EntityTemplate(new ContentProducer() {

public void writeTo(final OutputStream outstream) throws IOException {
OutputStreamWriter writer = new OutputStreamWriter(outstream, "UTF-8");
writer.write("<html><body><h1>");
writer.write("File ");
writer.write(file.getPath());
writer.write(" not found");
writer.write("</h1></body></html>");
writer.flush();
}

});
body.setContentType("text/html; charset=UTF-8");
response.setEntity(body);
log.error("File " + file.getPath() + " not found");

} else if (!file.canRead() || file.isDirectory()) {

response.setStatusCode(HttpStatus.SC_FORBIDDEN);
EntityTemplate body = new EntityTemplate(new ContentProducer() {

public void writeTo(final OutputStream outstream) throws IOException {
OutputStreamWriter writer = new OutputStreamWriter(outstream, "UTF-8");
writer.write("<html><body><h1>");
writer.write("Access denied");
writer.write("</h1></body></html>");
writer.flush();
}

});
body.setContentType("text/html; charset=UTF-8");
response.setEntity(body);
log.error("Cannot read file " + file.getPath());

} else {

response.setStatusCode(HttpStatus.SC_OK);
FileEntity body = new FileEntity(file, "text/html");
response.setEntity(body);
log.debug("Serving file " + file.getPath());

}
}
}

static class EventLogger implements EventListener {

private final Log log=LogFactory.getLog("EventLogger");

public void connectionOpen(final NHttpConnection conn) {
log.debug("Connection open: " + conn);
}

public void connectionTimeout(final NHttpConnection conn) {
log.debug("Connection timed out: " + conn);
}

public void connectionClosed(final NHttpConnection conn) {
log.debug("Connection closed: " + conn);
}

public void fatalIOException(final IOException ex, final NHttpConnection conn) {
log.debug("I/O error: " + ex.getMessage());
}

public void fatalProtocolException(final HttpException ex, final NHttpConnection conn) {
log.debug("HTTP error: " + ex.getMessage());
}

}

}
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第二部份：客户端代码片段(使用了Axis1.4)
---------------------------------------------------------------------------------------------------------------------------
...by omit...

try
{
String endpoint = "http://localhost:8080/ws";

Service service = new Service();
Call call = (Call) service.createCall();

call.setTargetEndpointAddress(new java.net.URL(endpoint));
call.setOperationName("JWSendLog");

ret = (String) call.invoke(new Object[]{"cd8f0a5a585940aa8420fb439311656d","0","kagula uid","0"});
}catch(AxisFault af)
{
System.out.println("Reason:"+af.getFaultReason());
}catch (ServiceException se)
{
se.printStackTrace();
}catch(Exception e)
{
e.printStackTrace();
}
System.out.println("testSMSWebService_JWSendLog(...) ret="+ret);

...by omit...
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第三部份：请求SOAP样例
---------------------------------------------------------------------------------------------------------------------------
<?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<soapenv:Body>
<JWSendLog soapenv:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
<arg0 xsi:type="soapenc:string" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/">
cd8f0a5a585940aa8420fb439311656d
</arg0>
<arg1 xsi:type="soapenc:string" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/">0</arg1>
<arg2 xsi:type="soapenc:string" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/">kagula uid</arg2>
<arg3 xsi:type="soapenc:string" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/">中文参数测试</arg3>
</JWSendLog>
</soapenv:Body>
</soapenv:Envelope>
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第四部份：返回SOAP样例
---------------------------------------------------------------------------------------------------------------------------
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<soapenv:Body>
<Response xmlns="http://tempuri.org/">
<result xmlns="">&#x4F60;&#x597D;&#xFF01;&#x8FD9;&#x662F;&#x6211;&#x7684;&#x53CD;&#x9988;&#x4FE1;&#x606F;&#x3002;(Hello!It's my response msg.)
</result>
</Response>
</soapenv:Body>
</soapenv:Envelope>
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第五部份：使用简介
启动程序后，在地址栏中打入http://localhost:8080/ws也会返回xml形式的内容。
在地址栏中打入http://localhost:8080/index.html，WEB浏览器会去access你项目当前运行目录下的WebRoot目录下的index.html文件。
如果没有找到文件，返回，文件不存在的提示。

参考网站：
[1]axis官方网站
http://ws.apache.org/axis/
[2]httpcomponents项目官方网站
http://jakarta.apache.org/httpcomponents/

备注：
[1]代码经过修改，可以不依赖于Axis1.4提供的jar包
[2]本文中的代码，只有通过必要修改，才能作为WebService服务器使用。