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Package com.cjw.baidu.ocr;import lombok.extern.slf4j.Slf4j;import org.apache.commons.lang3.StringUtils;import java.io.*;import java.net.HttpURLConnection;import java.net.URL;import java.util.HashMap / * check the file type * @ author wucj * @ date 21:48:03 on October 16, 2019 * / @ Slf4jpublic class CheckFileType {/ * cache file header information-header information * / public static final HashMap mFileTypes = new HashMap (); static {/ / images mFileTypes.put ("FFD8FF", "jpg"); mFileTypes.put ("89504E47", "png") MFileTypes.put ("47494638", "gif"); mFileTypes.put ("49492A00", "tif"); mFileTypes.put ("424D", "bmp"); / / CAD mFileTypes.put ("41433130", "dwg"); mFileTypes.put ("38425053", "psd"); / / Diary mFileTypes.put ("7B5C727466", "rtf") MFileTypes.put ("3C3F786D6C", "xml"); mFileTypes.put ("68746D6C3E", "html"); / / email mFileTypes.put ("44656C69766572792D646174653A", "eml"); mFileTypes.put ("D0CF11E0", "doc"); / / excel2003 version file mFileTypes.put ("D0CF11E0", "xls"); mFileTypes.put ("5374616E64617264204A", "mdb") MFileTypes.put ("252150532D41646F6265", "ps"); mFileTypes.put ("255044462D312E", "pdf"); mFileTypes.put ("504B0304", "docx"); / / excel2007 above mFileTypes.put ("504B0304", "xlsx"); mFileTypes.put ("52617221", "rar"); mFileTypes.put ("57415645", "wav") MFileTypes.put ("41564920", "avi"); mFileTypes.put ("2E524D46", "rm"); mFileTypes.put ("000001BA", "mpg"); mFileTypes.put ("000001B3", "mpg"); mFileTypes.put ("6D6F6F76", "mov"); mFileTypes.put ("3026B2758E66CF11", "asf"); mFileTypes.put ("4D546864", "mid") MFileTypes.put ("1F8B08", "gz");} / * filePath gets the file type * @ param filePath file path * @ return * @ throws FileNotFoundException * / public static String getFileType (String filePath) throws FileNotFoundException {File file = new File (filePath); if (file.isDirectory ()) {throw new RuntimeException ("current path is a directory") } return getFileType (new FileInputStream (file));} / * url get file type * @ param fileUrl network file url * @ return * @ throws Exception * / public static String urlFileType (String fileUrl) throws Exception {log.info ("url: {} get file type", fileUrl); BufferedInputStream bis = null; HttpURLConnection urlconnection = null; URL url = null Url = new URL (fileUrl); urlconnection = (HttpURLConnection) url.openConnection (); urlconnection.connect (); String fileType = getFileType (urlconnection.getInputStream ()); log.info ("url: {} get file type: {}", fileUrl,fileType); return fileType;} / * * @ return file header information * @ author liang.pan *

* method description: obtain header information according to input stream * / public static String getFileType (InputStream inputStream) {return mFileTypes.get (getFileHeader (inputStream));} / * * @ return header information * method description: obtain header information according to input stream * / public static String getFileHeader (InputStream inputStream) {InputStream is = null; String value = null Try {is = inputStream; byte [] b = new byte [4]; / * * int read () reads a byte of data from this input stream. Int read (byte [] b) reads up to b.length * bytes of data from this input stream into a byte array. Int read (byte [] b, int off, int len) * reads up to len bytes of data from this input stream into a byte array. * / is.read (b, 0, b.length); value = bytesToHexString (b);} catch (Exception e) {} finally {if (null! = is) {try {is.close () } catch (IOException e) {} if (StringUtils.startsWith (value, "FFD8FF")) {value = value.substring (0,6);} return value } / * * @ param src byte array of files to read header information * @ return file header information *

* method description: convert the byte array of the file to be read header information into string type representation * / private static String bytesToHexString (byte [] src) {StringBuilder builder = new StringBuilder (); if (src = = null | | src.length

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