import org.apache.regexp.*;
import com.darwinsys.util.*;
import java.io.*;
import java.util.*;
/** A command-line grep-like program. Some options, and takes a pattern
* and an arbitrary list of text files.
*/
public class Grep2 {
/** The pattern we're looking for */
protected RE pattern;
/** The Reader for the current file */
protected BufferedReader d;
/** Are we to only count lines, instead of printing? */
protected boolean countOnly = false;
/** Are we to ignore case? */
protected boolean ignoreCase = false;
/** Are we to suppress print of filenames? */
protected boolean dontPrintFileName = false;
/** Are we to only list names of files that match? */
protected boolean listOnly = false;
/** are we to print line numbers? */
protected boolean numbered = false;
/** Are we to be silent bout errors? */
protected boolean silent = false;
/** are we to print only lines that DONT match? */
protected boolean inVert = false;
/** Construct a Grep2 object for each pattern, and run it
* on all input files listed in argv.
* Be aware that a few of the command-line options are not
* acted upon in this version - this is an exercise for the reader!
*/
public static void main(String[] argv) throws RESyntaxException {
if (argv.length < 1) {
System.err.println(
"Usage: Grep2 pattern [-chilsnv][-f pattfile][filename...]");
System.exit(1);
}
String pattern = null;
GetOpt go = new GetOpt("cf:hilnsv");
BitSet args = new BitSet();
char c;
while ((c = go.getopt(argv)) != 0) {
switch(c) {
case 'c':
args.set('C');
break;
case 'f':
try {
BufferedReader b = new BufferedReader(new FileReader(go.optarg()));
pattern = b.readLine();
b.close();
} catch (IOException e) {
System.err.println("Can't read pattern file " + go.optarg());
System.exit(1);
}
break;
case 'h':
args.set('H');
break;
case 'i':
args.set('I');
break;
case 'l':
args.set('L');
break;
case 'n':
args.set('N');
break;
case 's':
args.set('S');
break;
case 'v':
args.set('V');
break;
}
}
int ix = go.getOptInd();
if (pattern == null)
pattern = argv[ix-1];
Grep2 pg = new Grep2(pattern, args);
if (argv.length == ix)
pg.process(new InputStreamReader(System.in), "(standard input)");
else
for (int i=ix; i<argv.length; i++) {
try {
pg.process(new FileReader(argv[i]), argv[i]);
} catch(Exception e) {
System.err.println(e);
}
}
}
public Grep2(String arg, BitSet args) throws RESyntaxException {
// compile the regular expression
if (args.get('C'))
countOnly = true;
if (args.get('H'))
dontPrintFileName = true;
if (args.get('I'))
ignoreCase = true;
if (args.get('L'))
listOnly = true;
if (args.get('N'))
numbered = true;
if (args.get('S'))
silent = true;
if (args.get('V'))
inVert = true;
int caseMode = ignoreCase?RE.MATCH_CASEINDEPENDENT:RE.MATCH_NORMAL;
pattern = new RE(arg, caseMode);
}
/** Do the work of scanning one file
* @param ifile Reader Reader object already open
* @param fileName String Name of the input file
*/
public void process(Reader ifile, String fileName) {
String line;
int matches = 0;
try {
d = new BufferedReader(ifile);
while ((line = d.readLine()) != null) {
if (pattern.match(line)) {
if (countOnly)
matches++;
else {
if (!dontPrintFileName)
System.out.print(fileName + ": ");
System.out.println(line);
}
} else if (inVert) {
System.out.println(line);
}
}
if (countOnly)
System.out.println(matches + " matches in " + fileName);
d.close();
} catch (IOException e) { System.err.println(e); }
}
}
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