解析正则表达式中的.*，.*?，.+?的含义

import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.junit.jupiter.api.Test;

public class TestRegx {

 @Test
 public void testRegx(){

 String str = "<img src=``test.jpg` width=`60px` height=`80px`/>";

 String pattern1 = "src=`.*`";
 String pattern2 = "src=`.*?`";
 String pattern3 = "src=`.+?`";

 Pattern p1 = Pattern.compile(pattern1);
 Pattern p2 = Pattern.compile(pattern2);
 Pattern p3 = Pattern.compile(pattern3);

 Matcher m1 = p1.matcher(str);
 Matcher m2 = p2.matcher(str);
 Matcher m3 = p3.matcher(str);

 System.out.println("根据pattern1匹配的结果：");
 if (m1.find()) {
 for(int i=0; i<=m1.groupCount(); i++){
 System.out.println(m1.group(i));
 }
 }

 System.out.println("根据pattern2匹配的结果：");
 if (m2.find()) {
 for(int i=0; i<=m2.groupCount(); i++){
 System.out.println(m2.group(i));
 }
 }

 System.out.println("根据pattern3匹配的结果：");
 if (m3.find()) {
 for(int i=0; i<=m3.groupCount(); i++){
 System.out.println(m3.group(i));
 }
 }

 String[] str1 = p1.split(str);
 String[] str2 = p2.split(str);
 String[] str3 = p3.split(str);

 System.out.println("根据pattern1切分的结果");
 for (int i=0; i< str1.length; i++) {
 System.out.println(str1[i]);
 }

 System.out.println("根据pattern2切分的结果");
 for (int i=0; i< str2.length; i++) {
 System.out.println(str2[i]);
 }

 System.out.println("根据pattern3切分的结果");
 for (int i=0; i< str3.length; i++) {
 System.out.println(str3[i]);
 }
 }
}