/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.regex.Matcher; 
import java.util.regex.Pattern;
 
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String regex = "https?:\\\\?/\\\\?/\\S+"; 
        String string = "http:/\\/books.google.com\\/books\\/content?id=0DwKEBD5ZBUC&printsec=frontcover&img=1&zoom=5&source=gbs_api";
    if(string.matches(regex)) {
      System.out.println(string.replace("\\/", "/"));
}
	}
}

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