在《 WebService大講堂之Axis2(2):復(fù)合類型數(shù)據(jù)的傳遞 》中講過(guò),如果要傳遞二進(jìn)制文件(如圖像、音頻文件等),可以使用byte[]作為數(shù)據(jù)類型進(jìn)行傳遞,然后客戶端使用RPC方式進(jìn)行調(diào)用。這樣做只是其中的一種方法,除此之外,在客戶端還可以使用wsdl2java命令生成相應(yīng)的stub類來(lái)調(diào)用WebServicewsdl2java命令的用法詳見(jiàn)《WebService大講堂之Axis2(1):用POJO實(shí)現(xiàn)0配置的WebService》。
??? WebService類中包含byte[]類型參數(shù)的方法在wsdl2java生成的stub類中對(duì)應(yīng)的數(shù)據(jù)類型不再是byte[]類型,而是javax.activation.DataHandlerDataHandler類是專門用來(lái)映射WebService二進(jìn)制類型的。
??? 在
WebService類中除了可以使用byte[]作為傳輸二進(jìn)制的數(shù)據(jù)類型外,也可以使用javax.activation.DataHandler作為數(shù)據(jù)類型。不管是使用byte[],還是使用javax.activation.DataHandler作為WebService方法的數(shù)據(jù)類型,使用wsdl2java命令生成的stub類中相應(yīng)方法的類型都是javax.activation.DataHandler。而象使用.netdelphi生成的stub類的相應(yīng)方法類型都是byte[]。這是由于javax.activation.DataHandler類是Java特有的,對(duì)于其他語(yǔ)言和技術(shù)來(lái)說(shuō),并不認(rèn)識(shí)javax.activation.DataHandler類,因此,也只有使用最原始的byte[]了。
??? 下面是一個(gè)上傳二進(jìn)制文件的例子,
WebService類的代碼如下:

package?service;

import?java.io.InputStream;
import?java.io.OutputStream;
import?java.io.FileOutputStream;
import?javax.activation.DataHandler;

public?class?FileService
{
???
//??使用byte[]類型參數(shù)上傳二進(jìn)制文件
????public?boolean?uploadWithByte(byte[]?file,?String?filename)
????{
?????????FileOutputStream?fos?
=?null;
?????????
try
?????????{??????????????????????????
?????????????fos?
=?new?FileOutputStream(filename);????
?????????????fos.write(file);
?????????????fos.close();
?????????}
?????????
catch?(Exception?e)
?????????{
?????????????
return?false;
?????????}
?????????
finally
?????????{
?????????????
if?(fos?!=?null)
?????????????{
?????????????????
try
?????????????????{
?????????????????????fos.close();
?????????????????}
?????????????????
catch?(Exception?e)
?????????????????{
?????????????????}
?????????????}
?????????}
?????????
return?true;
????}
????
private?void?writeInputStreamToFile(InputStream?is,?OutputStream?os)?throws?Exception
????{
?????????
int?n?=?0;
?????????
byte[]?buffer?=?new?byte[8192];
?????????
while((n?=?is.read(buffer))?>?0)
?????????{
?????????????os.write(buffer,?
0,?n);
?????????}
????}
????
//??使用DataHandler類型參數(shù)上傳文件
????public?boolean?uploadWithDataHandler(DataHandler?file,?String?filename)
????{
????????
?????????FileOutputStream?fos?
=?null;
?????????
try
?????????{????????????
?????????????fos?
=?new?FileOutputStream(filename);???
?????????????
//??可通過(guò)DataHandler類的getInputStream方法讀取上傳數(shù)據(jù)
?????????????writeInputStreamToFile(file.getInputStream(),?fos);
?????????????fos.close();
?????????}
?????????
catch?(Exception?e)
?????????{
?????????????
return?false;
?????????}
?????????
finally
?????????{
?????????????
if?(fos?!=?null)
?????????????{
?????????????????
try
?????????????????{
?????????????????????fos.close();
?????????????????}
?????????????????
catch?(Exception?e)
?????????????????{
?????????????????}
?????????????}
?????????}
?????????
return?true;
????}
}

上面代碼在services.xml文件的配置代碼如下:

<service?name="fileService">
????
<description>
????????文件服務(wù)
????
</description>
????
<parameter?name="ServiceClass">
????????service.FileService?
????
</parameter>
????????
<messageReceivers>
????????
<messageReceiver?mep="http://www.w3.org/2004/08/wsdl/in-out"
????????????class
="org.apache.axis2.rpc.receivers.RPCMessageReceiver"?/>
????
</messageReceivers>
</service>


??? 如果使用
wsdl2java命令生成調(diào)用Java客戶端代碼,則需要?jiǎng)?chuàng)建DataHandler類的對(duì)象實(shí)例,代碼如下:

DataHandler?dh?=?new?DataHandler(new?FileDataSource(imagePath));

wsdl2java命令會(huì)為每一個(gè)方法生成一個(gè)封裝方法參數(shù)的類,類名為方法名(第一個(gè)字符大寫(xiě)),如uploadWithByte方法生成的類名為UploadWithByte。如果要設(shè)置file參數(shù)的值,可以使用UploadWithByte類的setFile方法,代碼如下:


UploadWithByte?uwb?=?new?UPloadWithByte();
uwb.setFile(dh);

最后是調(diào)用uploadWithByte方法,代碼如下(FileServiceStubwsdl2java生成的stub類名):


FileServiceStub?fss?=?new?FileServiceStub();
fss.uploadWithByte(uwb);

如果使用C#調(diào)用FileService,則file參數(shù)類型均為byte[],代碼如下:

MemoryStream?ms?=?new?MemoryStream();
Bitmap?bitmap?
=?new?Bitmap(picUpdateImage.Image);
bitmap.Save(ms,?System.Drawing.Imaging.ImageFormat.Jpeg);
service.fileService?fs?
=?new?WSC.service.fileService();
fs.uploadWithDataHandler(ms.ToArray());
fs.uploadWithByte(ms.ToArray());
?

其中picUpdateImagec#中加載圖像文件的picturebox控件。