java 正则表达式 过滤html标签

// TODO Auto-generated constructor stub

}
/**

*

* 基本功能：替换标记以正常显示

* <p>

*

* @param input

* @return String

*/

public String replaceTag(String input) {

if (!hasSpecialChars(input)) {

return input;

}

StringBuffer filtered = new StringBuffer(input.length());

char c;

for (int i = 0; i <= input.length() - 1; i++) {

c = input.charAt(i);

switch (c) {

case '<':

filtered.append("<");

break;

case '>':

filtered.append(">");

break;

case '"':

filtered.append(""");

break;

case '&':

filtered.append("&");

break;

default:

filtered.append(c);

}

}

return (filtered.toString());

}

/**

*

* 基本功能：判断标记是否存在

* <p>

*

* @param input

* @return boolean

*/

public boolean hasSpecialChars(String input) {

boolean flag = false;

if ((input != null) && (input.length() > 0)) {

char c;

for (int i = 0; i <= input.length() - 1; i++) {

c = input.charAt(i);

switch (c) {

case '>':

flag = true;

break;

case '<':

flag = true;

break;

case '"':

flag = true;

break;

case '&':

flag = true;

break;

}

}

}

return flag;

}

/**

*

* 基本功能：过滤所有以"<"开头以">"结尾的标签

* <p>

*

* @param str

* @return String

*/

public static String filterHtml(String str) {

Pattern pattern = Pattern.compile(regxpForHtml);

Matcher matcher = pattern.matcher(str);

StringBuffer sb = new StringBuffer();

boolean result1 = matcher.find();

while (result1) {

matcher.appendReplacement(sb, "");

result1 = matcher.find();

}

matcher.appendTail(sb);

return sb.toString();

}

/**

*

* 基本功能：过滤指定标签

* <p>

*

* @param str

* @param tag

* 指定标签

* @return String

*/

public static String fiterHtmlTag(String str, String tag) {

String regxp = "<\\s*" + tag + "\\s+([^>]*)\\s*>";

Pattern pattern = Pattern.compile(regxp);

Matcher matcher = pattern.matcher(str);

StringBuffer sb = new StringBuffer();

boolean result1 = matcher.find();

while (result1) {

matcher.appendReplacement(sb, "");

result1 = matcher.find();

}

matcher.appendTail(sb);

return sb.toString();

}

/**

*

* 基本功能：替换指定的标签

* <p>

*

* @param str

* @param beforeTag

* 要替换的标签

* @param tagAttrib

* 要替换的标签属性值

* @param startTag

* 新标签开始标记

* @param endTag

* 新标签结束标记

* @return String

* @如：替换img标签的src属性值为

*/

public static String replaceHtmlTag(String str, String beforeTag,

String tagAttrib, String startTag, String endTag) {

String regxpForTag = "<\\s*" + beforeTag + "\\s+([^>]*)\\s*>";

String regxpForTagAttrib = tagAttrib + "=\"([^\"]+)\"";

Pattern patternForTag = Pattern.compile(regxpForTag);

Pattern patternForAttrib = Pattern.compile(regxpForTagAttrib);

Matcher matcherForTag = patternForTag.matcher(str);

StringBuffer sb = new StringBuffer();

boolean result = matcherForTag.find();

while (result) {

StringBuffer sbreplace = new StringBuffer();

Matcher matcherForAttrib = patternForAttrib.matcher(matcherForTag

.group(1));

if (matcherForAttrib.find()) {

matcherForAttrib.appendReplacement(sbreplace, startTag

+ matcherForAttrib.group(1) + endTag);

}

matcherForTag.appendReplacement(sb, sbreplace.toString());

result = matcherForTag.find();

}

matcherForTag.appendTail(sb);

return sb.toString();

}

}