fileinputstream

问题 The question is similar to the following two questions. Java InputStream blocking read Why is the FileInputStream read() not blocking? But I still cannot fully understand it. So far I think the read() method in following code will block due to the empty file 'test.txt'. FileInputStream fis = new FileInputStream("c:/test.txt"); System.out.println(fis.read()); System.out.println("to the end"); Actually it will print -1, I want to know why. The javadoc says This method blocks if no input is yet

问题 For the purpose of a task I have to store an image into MySQL as a blob format (even though it would have been better and ideal to store the image path in the database and keep the image in a folder in localcopy). So far I have researched and couldn't find any answer that could help me, this is what I have done so far Soon as a button click, this will be fired: empdao.insertImage(fis); Image is populated on another even listener like this : static FileInputStream fis = null; static String

问题 For the purpose of a task I have to store an image into MySQL as a blob format (even though it would have been better and ideal to store the image path in the database and keep the image in a folder in localcopy). So far I have researched and couldn't find any answer that could help me, this is what I have done so far Soon as a button click, this will be fired: empdao.insertImage(fis); Image is populated on another even listener like this : static FileInputStream fis = null; static String

问题 In my application there are no of documents(pdf) for a particular tender. I need to create a zip file from those pdf files and allow user to download it. Application is done in JavaEE with struts and mysql. when user clicks the download button this action class gets called. The code does not give any exceptions but it does not prompt user to download anything either. Please help me find what is wrong in the code. Following is the source code of my action class.. public class ActDownloadDocZip

问题 In my application there are no of documents(pdf) for a particular tender. I need to create a zip file from those pdf files and allow user to download it. Application is done in JavaEE with struts and mysql. when user clicks the download button this action class gets called. The code does not give any exceptions but it does not prompt user to download anything either. Please help me find what is wrong in the code. Following is the source code of my action class.. public class ActDownloadDocZip

问题 I read a file from the database that is in a byte[] array, using the ByteArrayInputStream . InputStream input = new ByteArrayInputStream(lc.getTable()); For a further processing of the file I need a FileInputStream . But I don't want to save the file on the hard disk first to read it again. Can this be done or does the file have to be written out first? 回答1: Not really. Then the further processing is overspecified; it should only require an InputStream. One could create a temporary deleted-on

问题 I'm using this method to copy files . It works perfectly for all simple file types such as csv , txt , pdf etc . . . except xlsx . I don't know why Excel file doesn't want to be copied . It gets corrupted public static void copyFileFromTo(File source, File dest) { InputStream input = null; OutputStream output = null; try { input = new FileInputStream(source); output = new FileOutputStream(dest); byte[] buf = new byte[1024]; int bytesRead; while ((bytesRead = input.read(buf)) > 0) { output

问题 I have an issue with FileInputStream on Android with Kotlin and Okhttp. I want to post a video file by using an API, but if this file is bigger than 128mb I have to upload it chunk by chunk. So, in my request header I have to specified the Content-Range (Something like this: Content-Range bytes 0-10485759/189305151 ) And I need to post only this part of the file, that why I'm using FileInputStream, then repeat for each chunks. I'm also using FileInputStream to avoid to split the file locally

问题 I have an issue with FileInputStream on Android with Kotlin and Okhttp. I want to post a video file by using an API, but if this file is bigger than 128mb I have to upload it chunk by chunk. So, in my request header I have to specified the Content-Range (Something like this: Content-Range bytes 0-10485759/189305151 ) And I need to post only this part of the file, that why I'm using FileInputStream, then repeat for each chunks. I'm also using FileInputStream to avoid to split the file locally

问题 I have an issue with FileInputStream on Android with Kotlin and Okhttp. I want to post a video file by using an API, but if this file is bigger than 128mb I have to upload it chunk by chunk. So, in my request header I have to specified the Content-Range (Something like this: Content-Range bytes 0-10485759/189305151 ) And I need to post only this part of the file, that why I'm using FileInputStream, then repeat for each chunks. I'm also using FileInputStream to avoid to split the file locally