Java基于url获取host的两种步骤

需求：

基于url获取host，case如下：

http://snv.iteye.com/blog/1992991结果为snv.iteye.com

snv.iteye.com/blog/1992991结果为snv.iteye.com

https://snv.iteye.com/blog/1992991结果为snv.iteye.com

http://snv.iteye.html结果为“”

http://snv.iteye.htm结果为“”

snv.iteye.html结果为“”

teye.html结果为“”

http://www.iteye.com/blog/1992991结果为www.iteye.com

www.iteye.com/blog/1992991结果为www.iteye.com

https://www.iteye.com/blog/1992991结果为www.iteye.com

方法实现如下：

方法1：基于URI或者URL

依赖：

<dependency>
	<groupId>commons-lang</groupId>
	<artifactId>commons-lang</artifactId>
	<version>2.6</version>
</dependency>

代码：

private static String getHost(String url) {
	if (!(StringUtils.startsWithIgnoreCase(url, "http://") || StringUtils
			.startsWithIgnoreCase(url, "https://"))) {
		url = "http://" + url;
	}
	String returnVal = StringUtils.EMPTY;
	try {
		URI uri = new URI(url);
		returnVal = uri.getHost();
	} catch (Exception e) {
	}
	if ((StringUtils.endsWithIgnoreCase(returnVal, ".html") || StringUtils
			.endsWithIgnoreCase(returnVal, ".htm"))) {
		returnVal = StringUtils.EMPTY;
	}
	return returnVal;
}

方法2：基于正则

依赖：

<dependency>
	<groupId>commons-lang</groupId>
	<artifactId>commons-lang</artifactId>
	<version>2.6</version>
</dependency>

代码：

public static String getHost(String url) {
	if (!(StringUtils.startsWithIgnoreCase(url, "http://") || StringUtils
			.startsWithIgnoreCase(url, "https://"))) {
		url = "http://" + url;
	}

	String returnVal = StringUtils.EMPTY;
	try {
		Pattern p = Pattern.compile("(?<=//|)((\\w)+\\.)+\\w+");
		Matcher m = p.matcher(url);
		if (m.find()) {
			returnVal = m.group();
		}

	} catch (Exception e) {
	}
	if ((StringUtils.endsWithIgnoreCase(returnVal, ".html") || StringUtils
			.endsWithIgnoreCase(returnVal, ".htm"))) {
		returnVal = StringUtils.EMPTY;
	}
	return returnVal;
}