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@jakoblorz
Last active March 22, 2017 11:58
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short general purpose snippet on how to read and write to files in java 8
/**
MIT License
Copyright (c) 2017 Jakob Lorz
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.stream.Stream;
/**
* Contains methods to read a file using Streams
*/
public class FileStreamReader {
/**
* reads the contents of a file and returns them as String[]
* @param file path to the file to read
* @return String[] representing the lines of the file, can be null when error occured
*/
public static String[] readLinesAsArray(String file){
try(Stream<String> stream = Files.lines(Paths.get(file))){
return (String[]) stream.toArray();
} catch (IOException e){
e.printStackTrace();
return null;
}
}
/**
* reads the contents of a file and streams them
* @param file path to the file to read
* @return Stream contains the lines as strings
*/
public static Stream<String> readLinesAsStream(String file){
try(Stream<String> stream = Files.lines(Paths.get(file))){
return stream;
} catch (IOException e){
e.printStackTrace();
return null;
}
}
}
/**
MIT License
Copyright (c) 2017 Jakob Lorz
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/
import java.io.*;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.stream.Stream;
/**
* Contains methods to write to file using Streams
*/
public class FileStreamWriter {
/**
* writes a String[] to a file
* @param lines Array containing the lines for the file
* @param file path to the file to write to
* @param append attach the lines to the file -> false if overwrite is wanted
*/
public static void writeLinesFromArray(String[] lines, String file, boolean append){
try(FileWriter fileWriter = new FileWriter(file, append);
BufferedWriter bufferedStreamWriter = new BufferedWriter(fileWriter);
PrintWriter out = new PrintWriter(bufferedStreamWriter))
{
for(String line : lines){
out.println(line);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
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