com.alibaba.excel.util.FileUtils Maven / Gradle / Ivy
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package com.alibaba.excel.util;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;
import org.apache.poi.util.DefaultTempFileCreationStrategy;
import org.apache.poi.util.TempFile;
import com.alibaba.excel.exception.ExcelAnalysisException;
import com.alibaba.excel.exception.ExcelCommonException;
/**
*
* @author jipengfei
*/
public class FileUtils {
public static final String POI_FILES = "poifiles";
public static final String EX_CACHE = "excache";
/**
* If a server has multiple projects in use at the same time, a directory with the same name will be created under
* the temporary directory, but each project is run by a different user, so there is a permission problem, so each
* project creates a unique UUID as a separate Temporary Files.
*/
private static String tempFilePrefix =
System.getProperty(TempFile.JAVA_IO_TMPDIR) + File.separator + UUID.randomUUID().toString() + File.separator;
/**
* Used to store poi temporary files.
*/
private static String poiFilesPath = tempFilePrefix + POI_FILES + File.separator;
/**
* Used to store easy excel temporary files.
*/
private static String cachePath = tempFilePrefix + EX_CACHE + File.separator;
private static final int WRITE_BUFF_SIZE = 8192;
private FileUtils() {}
static {
// Create a temporary directory in advance
File tempFile = new File(tempFilePrefix);
createDirectory(tempFile);
tempFile.deleteOnExit();
// Initialize the cache directory
File cacheFile = new File(cachePath);
createDirectory(cacheFile);
cacheFile.deleteOnExit();
}
/**
* Reads the contents of a file into a byte array. * The file is always closed.
*
* @param file
* @return
* @throws IOException
*/
public static byte[] readFileToByteArray(final File file) throws IOException {
InputStream in = openInputStream(file);
try {
final long fileLength = file.length();
return fileLength > 0 ? IoUtils.toByteArray(in, (int)fileLength) : IoUtils.toByteArray(in);
} finally {
in.close();
}
}
/**
* Opens a {@link FileInputStream} for the specified file, providing better error messages than simply calling
* new FileInputStream(file).
*
* At the end of the method either the stream will be successfully opened, or an exception will have been thrown.
*
* An exception is thrown if the file does not exist. An exception is thrown if the file object exists but is a
* directory. An exception is thrown if the file exists but cannot be read.
*
* @param file
* @return
* @throws IOException
*/
public static FileInputStream openInputStream(final File file) throws IOException {
if (file.exists()) {
if (file.isDirectory()) {
throw new IOException("File '" + file + "' exists but is a directory");
}
if (file.canRead() == false) {
throw new IOException("File '" + file + "' cannot be read");
}
} else {
throw new FileNotFoundException("File '" + file + "' does not exist");
}
return new FileInputStream(file);
}
/**
* Write inputStream to file
*
* @param file
* @param inputStream
*/
public static void writeToFile(File file, InputStream inputStream) {
OutputStream outputStream = null;
try {
outputStream = new FileOutputStream(file);
int bytesRead;
byte[] buffer = new byte[WRITE_BUFF_SIZE];
while ((bytesRead = inputStream.read(buffer, 0, WRITE_BUFF_SIZE)) != -1) {
outputStream.write(buffer, 0, bytesRead);
}
} catch (Exception e) {
throw new ExcelAnalysisException("Can not create temporary file!", e);
} finally {
if (outputStream != null) {
try {
outputStream.close();
} catch (IOException e) {
throw new ExcelAnalysisException("Can not close 'outputStream'!", e);
}
}
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException e) {
throw new ExcelAnalysisException("Can not close 'inputStream'", e);
}
}
}
}
public static void createPoiFilesDirectory() {
File poiFilesPathFile = new File(poiFilesPath);
createDirectory(poiFilesPathFile);
TempFile.setTempFileCreationStrategy(new DefaultTempFileCreationStrategy(poiFilesPathFile));
poiFilesPathFile.deleteOnExit();
}
public static File createCacheTmpFile() {
return createDirectory(new File(cachePath + UUID.randomUUID().toString()));
}
public static File createTmpFile(String fileName) {
File directory = createDirectory(new File(tempFilePrefix));
return new File(directory, fileName);
}
/**
*
* @param directory
*/
private static File createDirectory(File directory) {
if (!directory.exists() && !directory.mkdirs()) {
throw new ExcelCommonException("Cannot create directory:" + directory.getAbsolutePath());
}
return directory;
}
/**
* delete file
*
* @param file
*/
public static void delete(File file) {
if (file.isFile()) {
file.delete();
return;
}
if (file.isDirectory()) {
File[] childFiles = file.listFiles();
if (childFiles == null || childFiles.length == 0) {
file.delete();
return;
}
for (int i = 0; i < childFiles.length; i++) {
delete(childFiles[i]);
}
file.delete();
}
}
public static String getTempFilePrefix() {
return tempFilePrefix;
}
public static void setTempFilePrefix(String tempFilePrefix) {
FileUtils.tempFilePrefix = tempFilePrefix;
}
public static String getPoiFilesPath() {
return poiFilesPath;
}
public static void setPoiFilesPath(String poiFilesPath) {
FileUtils.poiFilesPath = poiFilesPath;
}
public static String getCachePath() {
return cachePath;
}
public static void setCachePath(String cachePath) {
FileUtils.cachePath = cachePath;
}
}