/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.regex.*;
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String str = "This is \"a string\" and this is \"a \\\"nested\\\" string\""; 
    	Pattern ptrn = Pattern.compile("\"[^\"\\\\]*(?:\\\\.[^\"\\\\]*)*\"|\\S+");
    	Matcher matcher = ptrn.matcher(str);
    	while (matcher.find()) {
    		System.out.println(matcher.group(0));
    	}
	}
}

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