?? diskfileitem.java
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* @return The contents of the file, as a string. * * @todo Consider making this method throw UnsupportedEncodingException. */ public String getString() { byte[] rawdata = get(); String charset = getCharSet(); if (charset == null) { charset = DEFAULT_CHARSET; } try { return new String(rawdata, charset); } catch (UnsupportedEncodingException e) { return new String(rawdata); } } /** * A convenience method to write an uploaded item to disk. The client code * is not concerned with whether or not the item is stored in memory, or on * disk in a temporary location. They just want to write the uploaded item * to a file. * <p> * This implementation first attempts to rename the uploaded item to the * specified destination file, if the item was originally written to disk. * Otherwise, the data will be copied to the specified file. * <p> * This method is only guaranteed to work <em>once</em>, the first time it * is invoked for a particular item. This is because, in the event that the * method renames a temporary file, that file will no longer be available * to copy or rename again at a later time. * * @param file The <code>File</code> into which the uploaded item should * be stored. * * @throws Exception if an error occurs. */ public void write(File file) throws Exception { if (isInMemory()) { FileOutputStream fout = null; try { fout = new FileOutputStream(file); fout.write(get()); } finally { if (fout != null) { fout.close(); } } } else { File outputFile = getStoreLocation(); if (outputFile != null) { // Save the length of the file size = outputFile.length(); /* * The uploaded file is being stored on disk * in a temporary location so move it to the * desired file. */ if (!outputFile.renameTo(file)) { BufferedInputStream in = null; BufferedOutputStream out = null; try { in = new BufferedInputStream( new FileInputStream(outputFile)); out = new BufferedOutputStream( new FileOutputStream(file)); IOUtils.copy(in, out); } finally { if (in != null) { try { in.close(); } catch (IOException e) { // ignore } } if (out != null) { try { out.close(); } catch (IOException e) { // ignore } } } } } else { /* * For whatever reason we cannot write the * file to disk. */ throw new FileUploadException( "Cannot write uploaded file to disk!"); } } } /** * Deletes the underlying storage for a file item, including deleting any * associated temporary disk file. Although this storage will be deleted * automatically when the <code>FileItem</code> instance is garbage * collected, this method can be used to ensure that this is done at an * earlier time, thus preserving system resources. */ public void delete() { cachedContent = null; File outputFile = getStoreLocation(); if (outputFile != null && outputFile.exists()) { outputFile.delete(); } } /** * Returns the name of the field in the multipart form corresponding to * this file item. * * @return The name of the form field. * * @see #setFieldName(java.lang.String) * */ public String getFieldName() { return fieldName; } /** * Sets the field name used to reference this file item. * * @param fieldName The name of the form field. * * @see #getFieldName() * */ public void setFieldName(String fieldName) { this.fieldName = fieldName; } /** * Determines whether or not a <code>FileItem</code> instance represents * a simple form field. * * @return <code>true</code> if the instance represents a simple form * field; <code>false</code> if it represents an uploaded file. * * @see #setFormField(boolean) * */ public boolean isFormField() { return isFormField; } /** * Specifies whether or not a <code>FileItem</code> instance represents * a simple form field. * * @param state <code>true</code> if the instance represents a simple form * field; <code>false</code> if it represents an uploaded file. * * @see #isFormField() * */ public void setFormField(boolean state) { isFormField = state; } /** * Returns an {@link java.io.OutputStream OutputStream} that can * be used for storing the contents of the file. * * @return An {@link java.io.OutputStream OutputStream} that can be used * for storing the contensts of the file. * * @throws IOException if an error occurs. */ public OutputStream getOutputStream() throws IOException { if (dfos == null) { File outputFile = getTempFile(); dfos = new DeferredFileOutputStream(sizeThreshold, outputFile); } return dfos; } // --------------------------------------------------------- Public methods /** * Returns the {@link java.io.File} object for the <code>FileItem</code>'s * data's temporary location on the disk. Note that for * <code>FileItem</code>s that have their data stored in memory, * this method will return <code>null</code>. When handling large * files, you can use {@link java.io.File#renameTo(java.io.File)} to * move the file to new location without copying the data, if the * source and destination locations reside within the same logical * volume. * * @return The data file, or <code>null</code> if the data is stored in * memory. */ public File getStoreLocation() { return dfos.getFile(); } // ------------------------------------------------------ Protected methods /** * Removes the file contents from the temporary storage. */ protected void finalize() { File outputFile = dfos.getFile(); if (outputFile != null && outputFile.exists()) { outputFile.delete(); } } /** * Creates and returns a {@link java.io.File File} representing a uniquely * named temporary file in the configured repository path. The lifetime of * the file is tied to the lifetime of the <code>FileItem</code> instance; * the file will be deleted when the instance is garbage collected. * * @return The {@link java.io.File File} to be used for temporary storage. */ protected File getTempFile() { File tempDir = repository; if (tempDir == null) { tempDir = new File(System.getProperty("java.io.tmpdir")); } String fileName = "upload_" + UID + "_" + getUniqueId() + ".tmp"; File f = new File(tempDir, fileName); FileCleaner.track(f, this); return f; } // -------------------------------------------------------- Private methods /** * Returns an identifier that is unique within the class loader used to * load this class, but does not have random-like apearance. * * @return A String with the non-random looking instance identifier. */ private static String getUniqueId() { final int limit = 100000000; int current; synchronized (DiskFileItem.class) { current = counter++; } String id = Integer.toString(current); // If you manage to get more than 100 million of ids, you'll // start getting ids longer than 8 characters. if (current < limit) { id = ("00000000" + id).substring(id.length()); } return id; } /** * Returns a string representation of this object. * * @return a string representation of this object. */ public String toString() { return "name=" + this.getName() + ", StoreLocation=" + String.valueOf(this.getStoreLocation()) + ", size=" + this.getSize() + "bytes, " + "isFormField=" + isFormField() + ", FieldName=" + this.getFieldName(); } // -------------------------------------------------- Serialization methods /** * Writes the state of this object during serialization. * * @param out The stream to which the state should be written. * * @throws IOException if an error occurs. */ private void writeObject(ObjectOutputStream out) throws IOException { // Read the data if (dfos.isInMemory()) { cachedContent = get(); } else { cachedContent = null; dfosFile = dfos.getFile(); } // write out values out.defaultWriteObject(); } /** * Reads the state of this object during deserialization. * * @param in The stream from which the state should be read. * * @throws IOException if an error occurs. * @throws ClassNotFoundException if class cannot be found. */ private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException { // read values in.defaultReadObject(); OutputStream output = getOutputStream(); if (cachedContent != null) { output.write(cachedContent); } else { FileInputStream input = new FileInputStream(dfosFile); IOUtils.copy(input, output); dfosFile.delete(); dfosFile = null; } output.close(); cachedContent = null; }}
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