java.util.regex.Matcher.usePattern() 方法
描述
java.util.regex.Matcher.usePattern(Pattern newPattern) 方法更改了此 Matcher 用于查找匹配项的模式。
声明
以下是 java.util.regex.Matcher.usePattern(Pattern newPattern) 方法的声明。
public Matcher usePattern(Pattern newPattern)
参数
newPattern − 此匹配器使用的新模式。
返回值
此匹配器。
异常
IllegalArgumentException − 如果 newPattern 为 null。
示例
下面的例子展示了 java.util.regex.Matcher.usePattern(Pattern newPattern) 方法的用法。
package com.tutorialspoint;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class MatcherDemo {
private static String REGEX = "(a*b)(foo)";
private static String INPUT = "aabfooaabfooabfoob";
public static void main(String[] args) {
// create a pattern
Pattern pattern = Pattern.compile(REGEX);
// get a matcher object
Matcher matcher = pattern.matcher(INPUT);
while(matcher.find()) {
//Prints the start index of the subsequence captured by the given group.
System.out.println("Second Capturing Group, (foo) Match String start(): "+matcher.start(1));
}
matcher.reset();
matcher.usePattern(Pattern.compile("(a*b)(foob)"));
while(matcher.find()) {
//Prints the start index of the subsequence captured by the given group.
System.out.println("Second Capturing Group, (fooab) Match String start(): "+matcher.start(1));
}
}
}
让我们编译并运行上面的程序，这将产生以下结果 −
Second Capturing Group, (foo) Match String start(): 0 Second Capturing Group, (foo) Match String start(): 6 Second Capturing Group, (foo) Match String start(): 12 Second Capturing Group, (fooab) Match String start(): 12
