Question

for a Java project for a University Class I have a method that saves ASCII images as a uniline string and another method called toString rebuilds this ASCII image and returns as a string. When I run my program on the Eclipse my output looks on console alright and multiline, and there are line breaks where they should be. But when I run it with the command line with a redirected outputfile

java myprogram < input > output

the text in the output is uniline without line breaks

Here is the code of the method

public String toString(){

    String output = "";

    for(int i=0; i<height; i++){
        output=output+image.substring(i*width, i*width+width)+"\n";

        }
    return output;  
}

What should I do so I can get a multiline output text file

Answer 1

A faster solution with \r\n when Windows:

public String toString() {
    final String EOL = System.getProperty("line.separator");
    final int EOL_LENGTH = EOL.length();
    StringBuilder output = new StringBuilder(image.length() + EOL_LENGTH * height);
    output.append(image);
    for (int i = 0; i < height; i++) {
        output.insert(i*(width + EOL_LENGTH) + width, EOL);
    }
    return output.toString();  
}