问题
I'm writing a bit of code to run a shell script using process that loads and runs a file in terminal. The problem I'm having is getting the filename to be recognised by terminal due to the spaces, for example :
"$ ./run_file.sh foo bar.ss"
should be run in terminal as
"$ ./run_file.sh foo\ bar.ss"
Heres the code to change it replace it:
JPanel panel1 = new JPanel();
JButton button = new JButton("Run");
button.setAlignmentX( Component.CENTER_ALIGNMENT);
button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event){
run();
}
});
//button.setAlignmentX(0.5);
panel1.add(button);
panel1.add(Box.createVerticalGlue());
panel1.add(button);
menuB = new JMenuBar();
JMenu dropD = new JMenu("File");
menuB.add(dropD);
JMenuItem loadR = new JMenuItem("Load file");
JMenuItem quit = new JMenuItem("Quit");
dropD.add(loadR);
dropD.add(quit);
loadR.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event) {
JFileChooser fileopen = new JFileChooser();
int r= fileopen.showDialog(panel, "Load file");
if (r == JFileChooser.APPROVE_OPTION) {
File file = fileopen.getSelectedFile();
String string = file.toString();
string = string.replaceAll(" ", "\ ");
//String output = aa.replaceAll("/",Character.toString(File.separatorChar));
System.out.println(string);
loadFile = file;
}
}
});
I have been tried using String.replaceAll but get
java:66: illegal escape character
i realise that I can use File.separatorChar :
string = string.replaceAll(" ", Character.toString(File.separatorChar)+" ");
but this doesn't seem to replace anything... Any help would be much appreciated.
Thanks
回答1:
If you want to put the \
character (which is the escape character) inside a string, you'll need to escape it:
string = string.replaceAll (" ", "\\ ");
A single \
is a escape sequence leading character, such as with \n
(newline) or \r
(carriage return). The full list of single-character escapes is:
\b backspace
\t tab
\n linefeed (newline)
\f form feed
\r carriage return
\" double quote
\' single quote
\\ backslash
This is in addition to the octal escape sequences s such as \0
, \12
or \377
.
The reason why your separatorChar
solution won't work is because that gives you the separator char (/
under UNIX and its brethren), not the escape character \
that you need.
回答2:
If you want the string to contain an actual backslash you need to escape the backslash. Otherwise javac thinks you're trying to escape space, which doesn't need escaping:
string = string.replaceAll(" ", "\\ ");
Using this code, the second argument to the method will be a 2-character string: backslash followed by space. I assume that's what you want.
See section 3.10.6 of the Java Language Specification for more details of character/string literal escape sequences.
来源:https://stackoverflow.com/questions/9532596/llegal-escape-character-followed-by-a-space