replacing text on files recursively over directories

In very special ocations, when I'm programming, I need to recursively replace text of all files in directories. For example, you want to recursively replace the string "import org.foo.bar.Class1" with "org2.foo.bar.Class1" in all .java files, in a java source folder. I know this can be done with a relatively simple shell (bash) script using sed, grep, etc unix commands, but what about systems that doesn't have bash? Also, there is a program called rpl (http://www.laffeycomputer.com/rpl.html) which purpose is this but, unfortunately, didn't worked for me (I compiled it on my machine, but the command fails with an error message (couldn't allocate memory or simply doesn't finnish its execution). So I implemented this functionality in java. I tested it on large source folders and works quick and nice. I hope this can be helpful for somebody:



package org.sgx.utils;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

/**
* replace strings with new strings in multiple text files recursively over
* directories and supports limiting the search to specific file names.
*
* @author sgurin
*
*/
public class RPL {
public static void copyDirAndReplaceRecursively(File src, File dest,
String filter, String str, String replacement)
throws FileNotFoundException, IOException {
if (src.isDirectory()) {
dest.mkdirs();
File[] childs = src.listFiles();
for (int i = 0; i < childs.length; i++) {
File child = childs[i];
File destChild = new File(dest.getAbsolutePath()
+ File.separator + child.getName());
copyDirAndReplaceRecursively(child, destChild, filter, str,
replacement);
}
} else {
if (src.getName().contains(filter)) {
copyFileAnReplacetext(src, dest, str, replacement);
} else {
copyFileAnReplacetext(src, dest, null, null);
}
}

}

public static void copyFileAnReplacetext(File srcFile, File destFile,
String str, String replacement) throws FileNotFoundException,
IOException {
StringBuffer sb = new StringBuffer();
InputStream is = new FileInputStream(srcFile);
readFile(is, sb);
is.close();
String s = sb.toString();
if (str != null && replacement != null)
s = s.replace(str, replacement);
FileOutputStream os = new FileOutputStream(destFile);
os.write(s.getBytes());
os.close();
}

public static void readFile(InputStream in, StringBuffer sb)
throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(in));
String line = null;
while ((line = br.readLine()) != null) {
sb.append(line + "\n");
}
br.close();
}

// test
public static void main(String[] args) {
try {
File srcDir = new File(
"/home/sebastian/desarrollo/portal4/blogsJavas/src2"), destDir = new File(
"/home/sebastian/desarrollo/portal4/blogsJavas/src");
String str = "com.liferay.portlet.blogs", repl = "org.sgx.portlet.circulares";
FSUtils.copyDirAndReplaceRecursively(srcDir, destDir, ".java", str,
repl);

} catch (Exception e) {
e.printStackTrace();
}
}
}