Java 提取字符串中的项

我想在一个特定的字符串中提取Hello world当前我得到的第一个和最后一个事件。在一个字符串中有3（三）个Hello world文本，我想在每个特定的字符串中提取它们

String text="hellogfddfdfsdsworldhelloasaasasdasdggworldfdfdsdhellodasasddworld";
int x=text.indexOf("hello");
int y=text.indexOf("world");
String test=text.substring(x, y+4);
System.out.println(test);
x=text.indexOf("hello");
y=text.indexOf("world");
String test1=text.substring(x,y);
System.out.println(test1);
x=text.lastIndexOf("hello");
y=text.lastIndexOf("world);
String test2=text.substring(x, y);
System.out.println(test2);

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听起来像是正则表达式的工作。最简单的是

List<String> matchList = new ArrayList<String>();
Pattern regex = Pattern.compile(
    "hello # Match 'hello'\n" +
    ".*?   # Match 0 or more characters (any characters), as few as possible\n" +
    "world # Match 'world'", 
    Pattern.COMMENTS);
Matcher regexMatcher = regex.matcher(subjectString);
while (regexMatcher.find()) {
    matchList.add(regexMatcher.group());
} 

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请注意，如果模式可以嵌套，即。e

hello foo hello bar world baz world

不是真正的专家，但我认为

regex

可以满足您的需求！

Pattern regex = Pattern.compile(
    "hello # Match 'hello'\n" +
    "(.*?) # Match 0 or more characters (any characters), as few as possible\n" +
    "world # Match 'world'", 
    Pattern.COMMENTS);
Matcher regexMatcher = regex.matcher(subjectString);
while (regexMatcher.find()) {
    matchList.add(regexMatcher.group(1));
}