--- layout: default-layout title: FileFetcher - Dynamsoft Capture Vision Android Edition API Reference description: The class FileFetcher of Dynamsoft Capture Vision Android is a utility class that partitions a multi-page image file into multiple independent ImageData objects. keywords: file fetcher, Java, Kotlin needGenerateH3Content: true needAutoGenerateSidebar: true noTitleIndex: true --- # FileFetcher The `FileFetcher` class is a utility class that partitions a multi-page image file into multiple independent `ImageData` objects. It inherits the [`ImageSourceAdapter`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html) class so that you can set it as the input of `CaptureVisionRouter` with the API [`setInput`]({{ site.dcv_android_api }}capture-vision-router/multiple-file-processing.html#setinput). ## Definition *Namespace:* com.dynamsoft.utility *Assembly:* DynamsoftCaptureVisionBundle.aar ```java class FileFetcher ``` ## Methods | Method | Description | | ------ | ----------- | | [`setFile(filePath)`](#setfilefilepath) | Sets the file with a file path. | | [`setFile(fileBytes)`](#setfilefilebytes) | Sets the file with file bytes. | | [`setFile(imageData)`](#setfileimagedata) | Sets the file with a `ImageData` object. | | [`setFile(bitmap)`](#setfilebitmap) | Sets the file with a `Bitmap`. | | [`hasNextImageToFetch`](#hasnextimagetofetch) | Whether there is a next image to fetch. | | [`getImage`](#getimage) | Get the image data of the image. | | [`setPages`](#setpages) | Set the pages to read. | The following methods are inherited from [`ImageSourceAdapter`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html). | Method | Description | | ------ | ----------- | | [`addImageToBuffer`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#addimagetobuffer) | Adds an image to the internal buffer. | | [`clearBuffer`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#clearbuffer) | Clears all images from the buffer, resetting the state for new image fetching. | | [`getBufferOverflowProtectionMode`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#getbufferoverflowprotectionmode) | Get the current mode for handling buffer overflow. | | [`getColourChannelUsageType`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#getcolourchannelusagetype) | Get the current usage type for color channels in images. | | [`getImageCount`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#getimagecount) | Get the current number of images in the buffer. | | [`getImage`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#getimage) | Get a buffered image. Implementing classes should return a Promise that resolves with an instance of `DSImageData`. | | [`getMaxImageCount`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#getmaximagecount) | Get the maximum number of images that can be buffered. | | [`hasImage`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#hasimage) | Checks if an image with the specified ID is present in the buffer. | | [`hasNextImageToFetch`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#hasnextimagetofetch) | Determines whether there are more images available to fetch. | | [`isBufferEmpty`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#isbufferempty) | Determines whether the buffer is currently empty. | | [`setBufferOverflowProtectionMode`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#setbufferoverflowprotectionmode) | Sets the behavior for handling new incoming images when the buffer is full. | | [`setColourChannelUsageType`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#setcolourchannelusagetype) | Sets the usage type for color channels in images. | | [`setErrorListener`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#seterrorlistener) | Sets an error listener to receive notifications about errors that occur during image source operations. | | [`setMaxImageCount`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#setmaximagecount) | Sets the maximum number of images that can be buffered at any time. | | [`setNextImageToReturn(imageId)`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#setnextimagetoreturnimageid) | Sets the processing priority of a specific image. This can affect the order in which images are returned by getImage. | | [`setNextImageToReturn(imageId,keepInBuffer)`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#setnextimagetoreturnimageidkeepinbuffer) | Sets the processing priority of a specific image. This can affect the order in which images are returned by getImage. | | [`startFetching`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#startfetching) | Start fetching images from the source to the Video Buffer of ImageSourceAdapter. | | [`stopFetching`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#stopfetching) | Stop fetching images from the source to the Video Buffer of ImageSourceAdapter. | ### setFile(filePath) Sets the file with a file path. ```java void setFile(String filePath) throws UtilityException ``` **Parameters** `[in] filePath`: The file path. **Exception** | Error Code | Value | Description | | :--------- | :---- | :---------- | | EC_FILE_NOT_FOUND | -10005 | The file is not found. | | EC_FILE_TYPE_NOT_SUPPORTED | -10006 | The file type is not supported. | ### setFile(fileBytes) Sets the file with file bytes. ```java void setFile(byte[] fileBytes) throws UtilityException ``` **Parameters** `[in] fileBytes`: The file bytes. **Exception** | Error Code | Value | Description | | :--------- | :---- | :---------- | | EC_NULL_POINTER | -10002 | The fileBytes you input is null. | ### setFile(imageData) Sets the file with a `ImageData` object. ```java void setFile(ImageData imageData) throws UtilityException ``` **Parameters** `[in] buffer`: The image data. **Exception** | Error Code | Value | Description | | :--------- | :---- | :---------- | | EC_NULL_POINTER | -10002 | The ImageData object is null. | ### setFile(bitmap) Sets the file with an `android.graphics.Bitmap`. ```java void setFile(Bitmap bitmap) throws UtilityException ``` **Parameters** `[in] image`: An `android.graphics.Bitmap`. **Exception** | Error Code | Value | Description | | :--------- | :---- | :---------- | | EC_NULL_POINTER | -10002 | The image data of the Bitmap is null. | ### hasNextImageToFetch Whether there is a next image to fetch. ```java boolean hasNextImageToFetch() ``` **Return Value** A boolean value that indicates whether there is a next image to fetch. ### getImage Get the image data of the image. ```java ImageData getImage() ``` **Return Value** A `ImageData` as the image. ### setPages Set the pages to read. ```java void setPages(int[] pages) throws UtilityException; ``` **Parameters** `pages`: An array that contains all the pages to read. **Exception** | Error Code | Value | Description | | :--------- | :---- | :---------- | | EC_FILE_NOT_FOUND | -10005 | File not found. | | EC_FILE_TYPE_NOT_SUPPORTED | -10006 | The file type is not supported. | | EC_IMAGE_READ_FAILED | -10012 | Failed to read the image. | ## Inherited Methods The following methods are inherited from the [`ImageSourceAdapter`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html) class: | Method | Description | | ------ | ----------- | | [`hasNextImageToFetch`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#hasnextimagetofetch) | Determines whether there are more images left to fetch. | | [`setMaxImageCount`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#setmaximagecount) | Set the maximum capability of the Video Buffer. | | [`getMaxImageCount`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#getmaximagecount) | Get the property defines the maximum capability of the Video Buffer. | | [`setBufferOverflowProtectionMode`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#setbufferoverflowprotectionmode) | Sets a mode that determines the action to take when there is a new incoming image and the buffer is full. You can either block the Video Buffer or push out the oldest image and append a new one. | | [`getBufferOverflowProtectionMode`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#getbufferoverflowprotectionmode) | Get the buffer overflow protection mode. | | [`getImageCount`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#getimagecount) | Get the current image count in the Video Buffer. | | [`isBufferEmpty`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#isbufferempty) | Check whether the Video Buffer is empty. | | [`setColourChannelUsageType`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#setcolourchannelusagetype) | Set the usage type of a color channel in an image. | | [`getColourChannelUsageType`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#getcolourchannelusagetype) | Get the usage type of a color channel in an image. | | [`startFetching`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#startfetching) | Start fetching images from the source to the Video Buffer of ImageSourceAdapter. | | [`stopFetching`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#stopfetching) | Stop fetching images from the source to the Video Buffer of ImageSourceAdapter. | | [`getImage`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#getimage) | Get an image from the Video Buffer. | | [`setNextImageToReturn(imageId)`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#setnextimagetoreturnimageid) | Specify the next image that is returned by method getImage. | | [`setNextImageToReturn(imageId,keepInBuffer)`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#setnextimagetoreturnimageidkeepinbuffer) | Specify the next image that is returned by method getImage. | | [`hasImage`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#hasimage) | Check the availability of the specified image. | | [`addImageToBuffer`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#addimagetobuffer) | Adds an image to the buffer of the adapter. | | [`clearBuffer`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#clearbuffer) | Clears the image buffer. | | [`setErrorListener`]({{ site.dcv_android_api }}core/basic-structures/image-source-adapter.html#seterrorlistener) | Clears the image buffer. |