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@swankjesse
Created February 8, 2013 23:27
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Stream editor for Java nerds. Use Java regular expressions to break up lines, and Java format strings to put them back together again.
/*bin/mkdir /tmp/rip 2> /dev/null
javac -d /tmp/rip $0
java -cp /tmp/rip Rip "$@"
exit
*/
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Rip {
private final boolean skipUnmatched;
private final String newline;
private final String format;
private final Pattern pattern;
public Rip(boolean skipUnmatched, String newline, String format, Pattern pattern) {
this.skipUnmatched = skipUnmatched;
this.newline = newline;
this.format = format;
this.pattern = pattern;
}
private boolean rip() throws IOException {
boolean success = true;
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
String line;
while((line = in.readLine()) != null) {
Matcher matcher = pattern.matcher(line);
if (!matcher.find()) {
if (!skipUnmatched) {
System.err.println("Rip: Couldn't match \"" + line + "\"");
success = false;
}
continue;
}
Object[] groups = new Object[matcher.groupCount() + 1];
for (int g = 0; g < groups.length; g++) {
groups[g] = matcher.group(g);
}
try {
System.out.print(String.format(format, groups));
System.out.print(newline);
} catch (IllegalFormatException e) {
System.err.println("Rip: Couldn't format " + Arrays.asList(groups) + ", " + e.getMessage());
success = false;
}
}
return success;
}
public static void main(String[] args) throws IOException {
boolean skipUnmatched = false;
String newline = String.format("%n");
List<String> argsList = new ArrayList<String>(Arrays.asList(args));
for (Iterator<String> a = argsList.iterator(); a.hasNext(); ) {
String arg = a.next();
if ("-s".equals(arg) || "--skip_unmatched".equals(arg)) {
skipUnmatched = true;
a.remove();
}
if ("-n".equals(arg) || "--newline".equals(arg)) {
a.remove();
newline = a.next();
a.remove();
}
}
if (argsList.size() != 2) {
printUsage();
System.exit(1);
}
String regex = argsList.get(0);
String format = argsList.get(1);
Pattern pattern = Pattern.compile(regex);
Rip rip = new Rip(skipUnmatched, newline, format, pattern);
boolean success = rip.rip();
if (!success) {
System.err.println("Rip: Failed. Regex=\"" + regex + "\", Format=\"" + regex + "\"");
System.exit(-1);
}
}
public static void printUsage() {
System.out.println("Usage: Rip [flags] <regex> <format>");
System.out.println();
System.out.println(" regex: a Java regular expression, with groups");
System.out.println(" http://java.sun.com/javase/6/docs/api/java/util/regex/Pattern.html");
System.out.println(" you can (parenthesize) groups");
System.out.println(" \\s whitespace");
System.out.println(" \\S non-whitespace");
System.out.println(" \\w word characters");
System.out.println(" \\W non-word");
System.out.println();
System.out.println(" format: a Java Formatter string");
System.out.println(" http://java.sun.com/javase/6/docs/api/java/util/Formatter.html");
System.out.println(" %[argument_index$][flags][width][.precision]conversion");
System.out.println(" '%s', '%1$s' - the full matched text");
System.out.println(" '%2$s' the first (parenthesized) group");
System.out.println();
System.out.println(" Use 'single quotes' to prevent bash from interfering");
System.out.println();
System.out.println("flags:");
System.out.println(" --skip_unmatched: ignore input that doesn't match <regex>");
System.out.println(" -s:");
System.out.println();
System.out.println(" --newline <text>: use <text> to separate lines in output");
System.out.println(" -n <text>:");
System.out.println();
}
}
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