OAF数据库动态图片的实现

将图片写入数据库：

表字段类型为BLOB，在OAF中创建对应的Item，关联到相应VO属性,Item syle 设为MessageFileUpload

提交后就会自动保存到数据库中，使用PL/SQL Developer查看图片是否存储。

读取图片并在网页中显示：

流程：获取临时文件夹物理路径---从VO读取数据---使用IO流输出图片-修改Image Item的Source属性。

获取临时文件夹物理路径（CO代码）：

 

//物理路径
String phyPath = pageContext.getTemporaryImageLocation();
//相对路径
            String relPath = pageContext.getTemporaryImageSource();

/*以下两行注释用于生成唯一图片名，可视需要使用*/

            //String imageName = pageContext.generateUniqueImageName("UserIcon.gif",
            //OAWebBeanConstants.OA_TEMPORARY_IMAGE);
            String imageName = "UserIcon"+user_id+".gif";
            Serializable[] parameters = { user_id, phyPath, imageName };
            am.invokeMethod("queryUser", parameters);
//物理路径
String phyPath = pageContext.getTemporaryImageLocation();
//相对路径
            String relPath = pageContext.getTemporaryImageSource();

/*以下两行注释用于生成唯一图片名，可视需要使用*/

            //String imageName = pageContext.generateUniqueImageName("UserIcon.gif",
            //OAWebBeanConstants.OA_TEMPORARY_IMAGE);
            String imageName = "UserIcon"+user_id+".gif";
            Serializable[] parameters = { user_id, phyPath, imageName };
            am.invokeMethod("queryUser", parameters);

//物理路径 String phyPath = pageContext.getTemporaryImageLocation(); //相对路径 String relPath = pageContext.getTemporaryImageSource(); /*以下两行注释用于生成唯一图片名，可视需要使用*/ //String imageName = pageContext.generateUniqueImageName("UserIcon.gif", //OAWebBeanConstants.OA_TEMPORARY_IMAGE); String imageName = "UserIcon"+user_id+".gif"; Serializable[] parameters = { user_id, phyPath, imageName }; am.invokeMethod("queryUser", parameters); //物理路径 String phyPath = pageContext.getTemporaryImageLocation(); //相对路径 String relPath = pageContext.getTemporaryImageSource(); /*以下两行注释用于生成唯一图片名，可视需要使用*/ //String imageName = pageContext.generateUniqueImageName("UserIcon.gif", //OAWebBeanConstants.OA_TEMPORARY_IMAGE); String imageName = "UserIcon"+user_id+".gif"; Serializable[] parameters = { user_id, phyPath, imageName }; am.invokeMethod("queryUser", parameters);

 

从VO读取数据（AM代码）：

 

public void queryUser(String user_id, String phyPath,
                         String imageName) {
//此处调用了视图的查询方法
        getUserVO1().initQuery(new Number(Integer.parseInt(user_id)));
        OAViewObject vo = (OAViewObject)getUserVO1();
        BlobDomain image = null;
        if (vo.hasNext()) {
            Row row = vo.next();
            image = (BlobDomain)row.getAttribute("Icon");
            if (image != null)
                initImage(image, phyPath, imageName);
          }
    }
    public void queryUser(String user_id, String phyPath,
                         String imageName) {
//此处调用了视图的查询方法
        getUserVO1().initQuery(new Number(Integer.parseInt(user_id)));
        OAViewObject vo = (OAViewObject)getUserVO1();
        BlobDomain image = null;
        if (vo.hasNext()) {
            Row row = vo.next();
            image = (BlobDomain)row.getAttribute("Icon");
            if (image != null)
                initImage(image, phyPath, imageName);
          }
    }

public void queryUser(String user_id, String phyPath, String imageName) { //此处调用了视图的查询方法 getUserVO1().initQuery(new Number(Integer.parseInt(user_id))); OAViewObject vo = (OAViewObject)getUserVO1(); BlobDomain image = null; if (vo.hasNext()) { Row row = vo.next(); image = (BlobDomain)row.getAttribute("Icon"); if (image != null) initImage(image, phyPath, imageName); } } public void queryUser(String user_id, String phyPath, String imageName) { //此处调用了视图的查询方法 getUserVO1().initQuery(new Number(Integer.parseInt(user_id))); OAViewObject vo = (OAViewObject)getUserVO1(); BlobDomain image = null; if (vo.hasNext()) { Row row = vo.next(); image = (BlobDomain)row.getAttribute("Icon"); if (image != null) initImage(image, phyPath, imageName); } }

 

使用IO流输出图片（AM代码）：

 

private void initImage(BlobDomain image, String phyPath,
                           String imageName) {
        File directory = new File(phyPath);
        if (!directory.exists())
            directory.mkdirs();
        File imageFile = new File(directory, imageName);
        try {
            fromInputToOutput(image.getBinaryStream(),
                              new FileOutputStream(imageFile));
        } catch (Exception exception) {
            exception.printStackTrace();
        }
//DEBUG专用，看看路径对不对
        System.out.println(imageFile.getAbsolutePath());
    }

/*复制方法，图片大可以增大byte块*/
    public void fromInputToOutput(InputStream inputstream,
                                  OutputStream outputstream) throws IOException {
        byte abyte0[] = new byte[255];
        for (int i = 255; i == 255; ) {
            i = inputstream.read(abyte0);
            if (i < 0)
                break;
            outputstream.write(abyte0, 0, i);
        }
        outputstream.close();
        inputstream.close();
    }
    private void initImage(BlobDomain image, String phyPath,
                           String imageName) {
        File directory = new File(phyPath);
        if (!directory.exists())
            directory.mkdirs();
        File imageFile = new File(directory, imageName);
        try {
            fromInputToOutput(image.getBinaryStream(),
                              new FileOutputStream(imageFile));
        } catch (Exception exception) {
            exception.printStackTrace();
        }
//DEBUG专用，看看路径对不对
        System.out.println(imageFile.getAbsolutePath());
    }

/*复制方法，图片大可以增大byte块*/
    public void fromInputToOutput(InputStream inputstream,
                                  OutputStream outputstream) throws IOException {
        byte abyte0[] = new byte[255];
        for (int i = 255; i == 255; ) {
            i = inputstream.read(abyte0);
            if (i < 0)
                break;
            outputstream.write(abyte0, 0, i);
        }
        outputstream.close();
        inputstream.close();
    }

private void initImage(BlobDomain image, String phyPath, String imageName) { File directory = new File(phyPath); if (!directory.exists()) directory.mkdirs(); File imageFile = new File(directory, imageName); try { fromInputToOutput(image.getBinaryStream(), new FileOutputStream(imageFile)); } catch (Exception exception) { exception.printStackTrace(); } //DEBUG专用，看看路径对不对 System.out.println(imageFile.getAbsolutePath()); } /*复制方法，图片大可以增大byte块*/ public void fromInputToOutput(InputStream inputstream, OutputStream outputstream) throws IOException { byte abyte0[] = new byte[255]; for (int i = 255; i == 255; ) { i = inputstream.read(abyte0); if (i < 0) break; outputstream.write(abyte0, 0, i); } outputstream.close(); inputstream.close(); } private void initImage(BlobDomain image, String phyPath, String imageName) { File directory = new File(phyPath); if (!directory.exists()) directory.mkdirs(); File imageFile = new File(directory, imageName); try { fromInputToOutput(image.getBinaryStream(), new FileOutputStream(imageFile)); } catch (Exception exception) { exception.printStackTrace(); } //DEBUG专用，看看路径对不对 System.out.println(imageFile.getAbsolutePath()); } /*复制方法，图片大可以增大byte块*/ public void fromInputToOutput(InputStream inputstream, OutputStream outputstream) throws IOException { byte abyte0[] = new byte[255]; for (int i = 255; i == 255; ) { i = inputstream.read(abyte0); if (i < 0) break; outputstream.write(abyte0, 0, i); } outputstream.close(); inputstream.close(); }

 

修改Image Item的Source属性（CO代码）

 

OAImageBean image =
    (OAImageBean)webBean.findIndexedChildRecursive("Icon");
if (image != null) {
    image.setSource(relPath + imageName);}
                OAImageBean image =
                    (OAImageBean)webBean.findIndexedChildRecursive("Icon");
                if (image != null) {
                    image.setSource(relPath + imageName);}

OAImageBean image = (OAImageBean)webBean.findIndexedChildRecursive("Icon"); if (image != null) { image.setSource(relPath + imageName);} OAImageBean image = (OAImageBean)webBean.findIndexedChildRecursive("Icon"); if (image != null) { image.setSource(relPath + imageName);}

 

注解:

1.如果不需要显示图片，而只是提供下载，那么使用MessageDownload会容易得多（无需手动输出）

2.Image Item也可以用代码创建。

3.由于OAF默认的图片文件夹是在OA_MEDIA下，如果使用视图的临时变量作为Image Item的 Image URL引用，图片地址会错误

4.将图片存储于数据库中管理不易，性能也不如直接保存图片URL的好

5.生成的图片不论原格式是JPG.PNG或是GIF，统一为GIF浏览器也可以显示出来

6.此代码没有做安全处理，包括上传文件大小和文件类型