org.vertexium.util.AutoDeleteFileInputStream Maven / Gradle / Ivy
package org.vertexium.util;
import com.google.common.annotations.VisibleForTesting;
import java.io.*;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.StandardCopyOption;
/**
* An AutoDeleteFileInputStream deletes its underlying file when the stream is closed.
*/
public class AutoDeleteFileInputStream extends FileInputStream {
private final File file;
/**
* Create an AutoDeleteFileInputStream from an existing file.
*/
public AutoDeleteFileInputStream(File file) throws FileNotFoundException {
super(file);
this.file = file;
}
/**
* Create an AutoDeleteFileInputStream by copying the contents of another InputStream into a temporary file.
* copyFromStream is closed immediately after being copied. The temporary file will be deleted when this
* AutoDeleteFileInputStream is closed.
*/
public AutoDeleteFileInputStream(InputStream copyFromStream) throws IOException {
this(copyToTempFile(copyFromStream));
}
private static File copyToTempFile(InputStream inputStream) throws IOException {
try {
Path tempPath = Files.createTempFile(AutoDeleteFileInputStream.class.getSimpleName(), null);
Files.copy(inputStream, tempPath, StandardCopyOption.REPLACE_EXISTING);
File tempFile = tempPath.toFile();
tempFile.deleteOnExit();
return tempFile;
} finally {
inputStream.close();
}
}
@Override
public void close() throws IOException {
try {
super.close();
} finally {
if (file.exists()) {
file.delete();
}
}
}
public long getFileLength() {
return file.length();
}
@VisibleForTesting
File getFile() {
return file;
}
}