使用正则表达式获取字符串中模式的索引

Use Matcher:

public static void printMatches(String text, String regex) {
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(text);
// Check all occurrences
while (matcher.find()) {
System.out.print("Start index: " + matcher.start());
System.out.print(" End index: " + matcher.end());
System.out.println(" Found: " + matcher.group());
}
}

import java.util.regex.Matcher;
import java.util.regex.Pattern;


public class RegexMatches
{
public static void main( String args[] ){


// String to be scanned to find the pattern.
String line = "This order was places for QT3000! OK?";
String pattern = "(.*)(\\d+)(.*)";


// Create a Pattern object
Pattern r = Pattern.compile(pattern);


// Now create matcher object.
Matcher m = r.matcher(line);
if (m.find( )) {
System.out.println("Found value: " + m.group(0) );
System.out.println("Found value: " + m.group(1) );
System.out.println("Found value: " + m.group(2) );
} else {
System.out.println("NO MATCH");
}
}
}

Result

Found value: This order was places for QT3000! OK?
Found value: This order was places for QT300
Found value: 0

special edition answer from Jean Logeart

public static int[] regExIndex(String pattern, String text, Integer fromIndex){
Matcher matcher = Pattern.compile(pattern).matcher(text);
if ( ( fromIndex != null && matcher.find(fromIndex) ) || matcher.find()) {
return new int[]{matcher.start(), matcher.end()};
}
return new int[]{-1, -1};
}