使用Axis2传输附件(AXIS2 MTOM)
本文介绍如何使用Axis2
传递附件。
author: ZJ 07-5-7
Blog: [url]http://zhangjunhd.blog.51cto.com/[/url]
1
．工作环境
IDE: Eclipse 3.1.2
jdk: jdk 1.5.0 _04
Tomcat: apache-tomcat- 5.0.28
AXIS2:1.0(war
版本和
bin
版本
)
2
．实现
在
Eclipse
新建一个动态
web
工程，在
WEB-INF\lib
下加入
axis2
所需的
jar
包。
本例的是一个系统的用户上传下载图片格式文件的例子，每次上传出携带附件外，还包括文件名
,
文件类型。此
webservice
实现的
2
个功能就是
upload, download.
AXIS2
的
webservice
发布的时候是打包成
xxx.aar
发布的，
xxx.aar
展开后的目录结构为
--
--META-INF
services.xml
--
包含
server
端实现的
class(
目录跟
package
是一样的结构
)
3
．服务器端FileTransferServer.java
|
package sample;
import org.apache.axiom.attachments.utils.IOUtils;
import org.apache.axiom.om.OMAbstractFactory;
import org.apache.axiom.om.OMElement;
import org.apache.axiom.om.OMFactory;
import org.apache.axiom.om.OMNamespace;
import org.apache.axiom.om.OMText;
import org.apache.axis2.AxisFault;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.util.Iterator;
import javax.activation.DataHandler;
import javax.activation.FileDataSource;
public class FileTransferServer {
public static final String TMP_PATH = "D:/temp";
public OMElement upload(OMElement element) throws Exception {
OMElement _fileContent = null;//
文件内容
OMElement _fileName = null;//
文件名
OMElement _fileType = null;//
文件类型
System.out.println("The element for upload: " + element);
for (Iterator _iterator = element.getChildElements(); _iterator
.hasNext();) {
OMElement _ele = (OMElement) _iterator.next();
if (_ele.getLocalName().equalsIgnoreCase("fileContent")) {
_fileContent = _ele;
}
if (_ele.getLocalName().equalsIgnoreCase("fileName")) {
_fileName = _ele;
}
if (_ele.getLocalName().equalsIgnoreCase("fileType")) {
_fileType = _ele;
}
}
if (_fileContent == null || _fileType == null) {
throw new AxisFault("Either Image or FileName is null");
}
OMText binaryNode = (OMText) _fileContent.getFirstOMChild();
String fileName = _fileName.getText();
String fileType = _fileType.getText();
String storeDir = TMP_PATH + "/" + "tempTest";
File dir = new File(storeDir);
if (!dir.exists()) {
dir.mkdir();
}
String filePath = storeDir + "/" + fileName + "." + fileType;
File uploadFile = new File(filePath);
if (uploadFile.exists()) {
filePath = storeDir + "/" + fileName + "(1)" + "." + fileType;
uploadFile = new File(filePath);
}
// Extracting the data and saving
DataHandler actualDH;
actualDH = (DataHandler) binaryNode.getDataHandler();
FileOutputStream imageOutStream = new FileOutputStream(uploadFile);
InputStream is = actualDH.getInputStream();
imageOutStream.write(IOUtils.getStreamAsByteArray(is));
// setting response
OMFactory fac = OMAbstractFactory.getOMFactory();
OMNamespace ns = fac.createOMNamespace("http://example.org/filedata",
"fd");
OMElement ele = fac.createOMElement("response", ns);
ele.setText("true");
return ele;
}
public OMElement download(OMElement element) throws Exception {
System.out.println("The element for download: " + element);
OMElement _userName = null;
OMElement _fileName = null;
OMElement _fileType = null;
for (Iterator _iterator = element.getChildElements(); _iterator
.hasNext();) {
OMElement _ele = (OMElement) _iterator.next();
if (_ele.getLocalName().equalsIgnoreCase("userName")) {
_userName = _ele;
}
if (_ele.getLocalName().equalsIgnoreCase("fileName")) {
_fileName = _ele;
}
if (_ele.getLocalName().equalsIgnoreCase("fileType")) {
_fileType = _ele;
}
}
String userName = _userName.getText();
String fileName = _fileName.getText();
String fileType = _fileType.getText();
String filePath = TMP_PATH + "/" + userName + "/" + fileName + "."
+ fileType;
System.out.println("The filePath for download: " + filePath);
FileDataSource dataSource = new FileDataSource(filePath);
DataHandler expectedDH = new DataHandler(dataSource);
OMFactory fac = OMAbstractFactory.getOMFactory();
OMNamespace ns = fac.createOMNamespace("http://example.org/filedata",
"fd");
OMText textData = fac.createOMText(expectedDH, true);
OMElement ele = fac.createOMElement("response", ns);
ele.addChild(textData);
return ele;
}
}
|
4.services.xml
|
<?xml version="1.0" encoding="UTF-8"?>
<service name="FileOperation">
<description>
This is a sample Web Service with two operations,echo and ping.
</description>
<parameter name="ServiceClass" locked="false">sample.FileTransferServer</parameter>
<operation name="upload">
<actionMapping>urn:upload</actionMapping>
<messageReceiver class="org.apache.axis2.receivers.RawXMLINOutMessageReceiver"/>
</operation>
<operation name="download">
<actionMapping>urn:download</actionMapping>
<messageReceiver class="org.apache.axis2.receivers.RawXMLINOutMessageReceiver"/>
</operation>
</service>
|
将这两个文件打包并部署到
Tomcat
上（略）。
5
．测试
FileTransferClient.java
|
package sample;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import javax.activation.DataHandler;
import javax.activation.FileDataSource;
import org.apache.axiom.attachments.utils.IOUtils;
import org.apache.axiom.om.OMAbstractFactory;
import org.apache.axiom.om.OMElement;
import org.apache.axiom.om.OMFactory;
import org.apache.axiom.om.OMNamespace;
import org.apache.axiom.om.OMText;
import org.apache.axiom.soap.SOAP11Constants;
import org.apache.axis2.AxisFault;
import org.apache.axis2.Constants;
import org.apache.axis2.addressing.EndpointReference;
import org.apache.axis2.client.Options;
import org.apache.axis2.client.ServiceClient;
public class FileTransferClient {
private static EndpointReference targetEPR =
new EndpointReference("http://127.0.0.1:8080/axis2/services/FileOperation");
public static boolean upload(String fileName, File file, String fileType) {
try {
OMElement data = buildUploadEnvelope(fileName, file, fileType);
Options options = buildOptions();
ServiceClient sender = new ServiceClient();
sender.setOptions(options);
System.out.println("The data in method upload: "+data);
OMElement ome = sender.sendReceive(data);
System.out.println("Convert the data to element in method upload: "+ome);
String b = ome.getText();
return Boolean.parseBoolean(b);
}
catch(Exception e) {
e.printStackTrace();
}
return false;
}
public static boolean download(String userName, String fileName, String fileType) {
try {
OMElement data = buildDownloadEnvelope(userName, fileName, fileType);
Options options = buildOptions();
ServiceClient sender = new ServiceClient();
sender.setOptions(options);
System.out.println("The data in method download: "+data);
OMElement ome = sender.sendReceive(data);
System.out.println("Convert the data to element in method download: "+ome);
OMText binaryNode = (OMText) ome.getFirstOMChild();
binaryNode.setOptimize(true); //
必须加此句，否则会出现
ContentID is null
的异常
!
DataHandler actualDH = (DataHandler) binaryNode.getDataHandler();
FileOutputStream imageOutStream = new FileOutputStream("D:/userTemp/xx.gif");
InputStream is = actualDH.getInputStream();
imageOutStream.write(IOUtils.getStreamAsByteArray(is));
return true;
}
catch(Exception e) {
e.printStackTrace();
}
return false;
}
private static OMElement buildUploadEnvelope(String fileName, File file, String fileType) {
DataHandler expectedDH;
OMFactory fac = OMAbstractFactory.getOMFactory();
OMNamespace omNs = fac.createOMNamespace("http://example.org/filedata", "fd");
OMElement data = fac.createOMElement("upload", omNs);
OMElement fileContent = fac.createOMElement("fileContent", omNs);
FileDataSource dataSource = new FileDataSource(file);
expectedDH = new DataHandler(dataSource);
OMText textData = fac.createOMText(expectedDH, true);
fileContent.addChild(textData);
OMElement _fileName = fac.createOMElement("fileName", omNs);
_fileName.setText(fileName);
OMElement _fileType = fac.createOMElement("fileType", omNs);
_fileType.setText(fileType);
data.addChild(_fileName);
data.addChild(_fileType);
data.addChild(fileContent);
return data;
}
private static OMElement buildDownloadEnvelope(String userName, String fileName, String fileType) {
OMFactory fac = OMAbstractFactory.getOMFactory();
OMNamespace omNs = fac.createOMNamespace("http://example.org/filedata", "fd");
OMElement data = fac.createOMElement("download", omNs);
OMElement _userName = fac.createOMElement("userName", omNs);
_userName.setText(userName);
OMElement _fileName = fac.createOMElement("fileName", omNs);
_fileName.setText(fileName);
OMElement _fileType=fac.createOMElement("fileType", omNs);
_fileType.setText(fileType);
data.addChild(_userName);
data.addChild(_fileName);
data.addChild(_fileType);
return data;
}
private static Options buildOptions() throws AxisFault {
Options options = new Options();
options.setSoapVersionURI(SOAP11Constants.SOAP_ENVELOPE_NAMESPACE_URI);
options.setTo(targetEPR);
// enabling MTOM in the client side
options.setProperty(Constants.Configuration.ENABLE_MTOM, Constants.VALUE_TRUE);
options.setTransportInProtocol(Constants.TRANSPORT_HTTP);
return options;
}
public static void main(String agrs[]) {
String file = "D:/userTemp/ya.gif";
String fn = "testUser";
String ft="gif";
boolean rtv = upload(fn,new File(file),ft);
System.out.println("is upload success: "+rtv);
String un="zj";
String downfn="1";
if(download(un,downfn,ft)){
System.out.println("download success.");
}
else System.out.println("download fail.");
System.out.println("Client main end.");
}
}
|
6.
结果
察看
soap
消息，我们可以发现
|
<fd:upload xmlns:fd="http://example.org/filedata">
<fd:fileName>testUser</fd:fileName>
<fd:fileType>gif</fd:fileType>
<fd:fileContent>RHQMLJJ4/AMZkEBAEAOw
（省略部分
2
进制代码）
</fd:fileContent>
</fd:upload>
Convert the data to element in method upload:
<fd:response xmlns:fd=http://example.org/filedata xmlns:tns="http://ws.apache.org/axis2">true</fd:response>
The data in method download:
<fd:download xmlns:fd="http://example.org/filedata">
<fd:userName>zj</fd:userName>
<fd:fileName>1</fd:fileName>
<fd:fileType>gif</fd:fileType>
</fd:download>
Convert the data to element in method download:
<fd:response xmlns:fd="http://example.org/filedata" xmlns:tns="http://ws.apache.org/axis2">
eIqGRwjkQAAAOw==
（省略部分
2
进制代码）
</fd:response>
|
7
．代码分析
利用
Axis2
的
Mtom
发送附件应用了
builder
模式。要向一个
webserive
发送请求，首先就要构建一个请求的
Envelope,Axis2
构建
Envelope
的时候是利用的
Axis2
的
AXIOM api(
就是
axis2
的
java object
和
xml
的映射处理机制
),
其编程模式和
DOM
差不多的
.
看这一段
:
|
private static OMElement buildUploadEnvelope(String mailboxnum, short greetingType, File file, String FileType) {
DataHandler expectedDH;
OMFactory fac = OMAbstractFactory.getOMFactory();
...
return data;
}
|
这一段其实是构建的
data
对像是这样一段
xml
的
java object
代表：
|
<fd:upload xmlns:fd="http://example.org/filedata">
<fd:fileName>testUser</fd:fileName>
<fd:fileType>gif</fd:fileType>
<fd:fileContent>RHQMLJJ4/AMZkEBAEAOw
（省略部分
2
进制代码）
</fd:fileContent>
</fd:upload>
|
其中的
Dwvc2VydmljZT4NCjwvZGVwbG95bWVudD4NCg0K
是要传送的文件的内容代表，至于什么编码，我没有深究。注意这一句
:
|
OMElement data = fac.createOMElement("upload", omNs);
|
这里的“
upload
”参数对应的是
webservice
的一个操作的名称，这个操作的名称是跟
webservice
的
server
端实现类的方法名和
services.xml
的所定义的
|
<operationname="upload">
<actionMapping>urn:upload</actionMapping>
<messageReceiverclass="org.apache.axis2.receivers.RawXMLINOutMessageReceiver"/>
</operation>
|
要一致的。
再看看这一段，
|
private static Options buildOptions() {
Options options = new Options();
...
return options;
}
|
这里构建的
Options
对象，顾名思义就是调用
webservice
的相应的选项：比如这里就指定了
Soap
协议为
1.1
版
,
指定了所请求的
service
的
EPR(
就是地址
)
，声明在
client
应用
MTOM
指定传输协议为
HTTP
。
构建好要传送的
data
和
options
后
,
所执行的代码为：
|
ServiceClient sender = new ServiceClient();
//
设定选项
sender.setOptions(options);
//
打印要传送的数据，为一段
xml
System.out.println(data);
//
传送数据，得到返回值
OMElement ome = sender.sendReceive(data);
//
打印返回值，为一段
xml
System.out.println(ome);
//
析取返回值中的数据
String b = ome.getText();
//
返回
return Boolean.parseBoolean(b);
|
可以发现，
server
端和
client
的中间传递数据都是通过
org.apache.axiom.om.OMElement
对象的，这个对象是一段
xml
的
java
对象映射。