Uploading and downloading files from database (BLOB) in Oracle ADF (12.1.3)

Hello all

This post is about a very simple requirement -file handling (uploading and downloading various types of file) in ADF and it is needed very often to store file in absolute server path (actual path) and download from there and I have posted about that previously

Uploading and downloading files from absolute server path

Now this post is about uploading and saving file in database BLOB column and downloading from there
See step by step implementation -

Show uploaded file (pdf/text/html/xml/image) content on page -Oracle ADF

Hello all
In previous post
Uploading and downloading files from absolute server path in Oracle ADF (12.1.3)
we saw that how can we upload any file to absolute server path and download same from there.
Uploading part is done using simple java code to write file to specified folder and downloading part is done using <af:fileDownloadActionListener>

Now in this post i am going to show that how can we display a file on page directly without downloading it.
So for this i am using same sample application that i have used in previous post , you can download it from here



See the additional steps to show file content on page-

• Create a servlet to parse file into output stream , this output stream will be used to show file content further.
  To create servlet right click on viewController project select New--->From Gallery-->Web Tier-->Servlet











• See servlet source code to parse file into outputStream



import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;

import javax.servlet.*;
import javax.servlet.http.*;

public class PreviewFileServlet extends HttpServlet {
    private static final String CONTENT_TYPE = "text/html; charset=UTF-8";

    public void init(ServletConfig config) throws ServletException {
        super.init(config);
    }

    /**
     * @param request
     * @param response
     * @throws ServletException
     * @throws IOException
     */
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String path = (request.getParameter("path"));

        OutputStream os = response.getOutputStream();
        //If path is null
        if (path.equalsIgnoreCase("No")) {
            path = "D:\\Document\\ItemImage\\Item.jpg";
        }
        if (request.getParameter("path") == "") {
            path = "D:\\Document\\ItemImage\\Item.jpg";
        }
        InputStream inputStream = null;

        try {
            File outputFile = new File(path);
            inputStream = new FileInputStream(outputFile);
            BufferedInputStream in = new BufferedInputStream(inputStream);
            int b;
            byte[] buffer = new byte[10240];
            while ((b = in.read(buffer, 0, 10240)) != -1) {
                os.write(buffer, 0, b);
            }

        } catch (Exception e) {

            System.out.println(e);
        } finally {
            if (os != null) {
                os.close();
            }
            if (inputStream != null) {
                inputStream.close();
            }

        }
    }
}



• Now open page in editor and drop an af:inlineFrame from component palette . inlineFrame is used to create a frame to show any external page or document just like as HTML iframe , it is loaded from source attribute
  So here i am using servlet as source attribute for this inlineFrame



<af:inlineFrame id="if2"
                                                    source="/previewfileservlet?path=#{bindings.Path.inputValue == null ? 'No' : bindings.Path.inputValue}"
                                                    inlineStyle="height:350px;width:800px;" sizing="preferred"/>


here path of document is added to pageDef bindings that is passed to servelt as parameter


• Now run this application and check it
  
  View Text File-

          View PDF File-

Thanks, Happy Learning :)

Post Related to file handling in Oracle ADF- 

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Uploading and showing image file from absolute server path -Orace ADF
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Creating pdf file using Apache PDFBox API in ADF Faces and opening it in new window -Oracle ADF
Download file from url using Oracle ADF & Java- Download Manager
Reading html source of a webpage (url) using Oracle ADF (af:richTextEditor) & Java

Uploading and downloading files from absolute server path in Oracle ADF (12.1.3)

Hello all
this post is about a very simple requirement -file handling (uploading and downloading various types of file) in ADF and it is needed very often to store file in absolute server path (actual path) and download from there

see step by step implementation -

• I have created a simple table in HR schema to store uploaded file name ,path and content type
See sql script for this table-

 CREATE TABLE "FILE_UPD_DWN" 
   ( "FILE_NAME" VARCHAR2(50 BYTE), 
 "PATH" VARCHAR2(100 BYTE), 
 "CONTENT_TYPE" VARCHAR2(500 BYTE)
   )



• Then prepare model using this table and drop on page as af:table, and an af:inputFile to select and upload file is used in page





• Then create a ValueChangeListener on inputFile component to upload file to an actual path on server, and after upload a row is inserted in table to keep record of uploaded files



Bean Method to Upload File-




    /**Method to upload file to actual path on Server*/
    private String uploadFile(UploadedFile file) {

        UploadedFile myfile = file;
        String path = null;
        if (myfile == null) {

        } else {
            // All uploaded files will be stored in below path
            path = "D://FileStore//" + myfile.getFilename();
            InputStream inputStream = null;
            try {
                FileOutputStream out = new FileOutputStream(path);
                inputStream = myfile.getInputStream();
                byte[] buffer = new byte[8192];
                int bytesRead = 0;
                while ((bytesRead = inputStream.read(buffer, 0, 8192)) != -1) {
                    out.write(buffer, 0, bytesRead);
                }
                out.flush();
                out.close();
            } catch (Exception ex) {
                // handle exception
                ex.printStackTrace();
            } finally {
                try {
                    inputStream.close();
                } catch (IOException e) {
                }
            }

        }
        //Returns the path where file is stored
        return path;
    }




AMImpl method to insert record in table for Uploaded file






    /**Method to set file path and name
     * @param name
     * @param path
     */
    public void setFileData(String name, String path,String contTyp) {
        ViewObject fileVo = this.getFileUpdDwn1();
        Row newRow = fileVo.createRow();
        newRow.setAttribute("FileName", name);
        newRow.setAttribute("Path", path);
        newRow.setAttribute("ContentType", contTyp);
        fileVo.insertRow(newRow);
        this.getDBTransaction().commit();
        fileVo.executeQuery();
    }




ValueChangeListener to execute all methods -






    /*****Generic Method to Get BindingContainer**/
    public BindingContainer getBindingsCont() {
        return BindingContext.getCurrent().getCurrentBindingsEntry();
    }

    /**
     * Generic Method to execute operation
     * */
    public OperationBinding executeOperation(String operation) {
        OperationBinding createParam = getBindingsCont().getOperationBinding(operation);
        return createParam;

    }

    /**Method to Upload File ,called on ValueChangeEvent of inputFile
     * @param vce
     */
    public void uploadFileVCE(ValueChangeEvent vce) {
        if (vce.getNewValue() != null) {
            //Get File Object from VC Event
            UploadedFile fileVal = (UploadedFile) vce.getNewValue();
            //Upload File to path- Return actual server path
            String path = uploadFile(fileVal);
            System.out.println(fileVal.getContentType());
            //Method to insert data in table to keep track of uploaded files
            OperationBinding ob = executeOperation("setFileData");
            ob.getParamsMap().put("name", fileVal.getFilename());
            ob.getParamsMap().put("path", path);
            ob.getParamsMap().put("contTyp", fileVal.getContentType());
            ob.execute();
            // Reset inputFile component after upload
            ResetUtils.reset(vce.getComponent());
        }
    }



• Now run application and select files and see- 





• See uploaded files in folder





• I have seen that developers often use servlet to download and open file in browser window using HTTP response , but no need to to do this as ADF provides built in component for this <af:fileDownloadActionListener> that automatically generate http response
• Now Upload part is complete , for download functionality added a link in table column and dropped an af:fileDownloadActionListener inside link and set properties for DownloadActionListener








• See the code in Download Listener



    /**Method to download file from actual path
     * @param facesContext
     * @param outputStream
     */
    public void downloadFileListener(FacesContext facesContext, OutputStream outputStream) throws IOException {
        //Read file from particular path, path bind is binding of table field that contains path
        File filed = new File(pathBind.getValue().toString());
        FileInputStream fis;
        byte[] b;
        try {
            fis = new FileInputStream(filed);

            int n;
            while ((n = fis.available()) > 0) {
                b = new byte[n];
                int result = fis.read(b);
                outputStream.write(b, 0, b.length);
                if (result == -1)
                    break;
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        outputStream.flush();
    }



• Now run application and see how Upload and download works 

Happy Learning :) Sample ADF Application

Next Post is this series - (Must Read)
Uploading mulitiple files to server path in Oracle ADF using af:inputFile
Uploading and downloading files from database (BLOB) in Oracle ADF

Exporting viewObject data in text file using af:fileDownloadActionListener in Oracle ADF (12.1.3)

Hello All
This post is about using af:fileDownloadActionListener to generate file on run-time, suppose i have a viewObject and i want to export it's data in CSV or plain text so for this requirement we can generate file at run-time and send it to client UI to download

What is af:fileDownloadActionListener-
as per oracle docs-
The fileDownloadActionListener tag is a declarative way to allow an action source (<commandButton>, <commandLink>, etc.) to programatically send the contents of a file to the user, optionally with a specific content type and filename. Since file downloads must be processed with an ordinary request - not XMLHttp AJAX requests - this tag forces partialSubmit to be false on the parent component, if it supports that attribute.
The fileDownloadActionListener uses the native (browser built-in) filedownload popup, so this popup cannot be configured.

In this post i am using Departments table of HR schema

• Prepare model part using Departments table and drop it on page as a table and add a button to UI for downloading





• drop af:fileDownloadActionListener as child of button and set it's property as contentType, method , fileName 





• Now see code written in download Listener-



    /**Method to get BindingsContainer for current page
     * @return
     */
    public BindingContainer getBindingsCont() {
        return BindingContext.getCurrent().getCurrentBindingsEntry();
    }

    /**Method to download ViewObject's data in plain text file
     * @param facesContext
     * @param outputStream
     * @throws UnsupportedEncodingException
     * @throws IOException
     */
    public void fileDownloadListener(FacesContext facesContext,
                                     OutputStream outputStream) throws UnsupportedEncodingException, IOException {
        OutputStreamWriter w = new OutputStreamWriter(outputStream, "UTF-8");
        //Get itertaor from bindings
        DCIteratorBinding deptIter = (DCIteratorBinding) getBindingsCont().get("Departments1Iterator");
        //Get ViewObject from Iterator
        ViewObjectImpl vo = (ViewObjectImpl) deptIter.getViewObject();
        ViewAttributeDefImpl[] attrDefs = vo.getViewAttributeDefImpls();
        int count = 0;
        RowSetIterator rsi = vo.createRowSetIterator(null);
        while (rsi.hasNext()) {
            Row nextRow = rsi.next();
            if (nextRow != null) {
                // Code to iterate over ViewObject's column to get all columns value at runtime
                for (ViewAttributeDefImpl attrDef : attrDefs) {
                    byte attrKind =
                        attrDefs[count].getAttributeKind(); //checks attribute kind for each element in an array of AttributeDefs
                    if (attrKind != AttributeDef.ATTR_ASSOCIATED_ROW &&
                        attrKind != AttributeDef.ATTR_ASSOCIATED_ROWITERATOR) {
                        String columnName = attrDef.getName();
                        w.write(columnName + " - " + nextRow.getAttribute(columnName) + "  ");
                    }
                }
                // Code to create new line text line for new Row
                w.write(System.getProperty("line.separator"));
            }
        }
        //Flush the writer after wrting file
        w.flush();
    }
}



• Run this application and click on download button, browser download box appears , open downloaded file and see how your data appears in text file, to export data in a pdf file you have to generate PDF file using some API then you can download it in same way

Cheers:) Happy Learning