截取HTML 文章，补充样式，防止出现样式乱套

<constant name="struts.ognl.allowStaticMethodAccess" value="true"/>

<s:property value="@com.tools.SubStringHTML@SubString(#this.content)" escape="false"/>

package com.tools;


public class SubStringHTML {

public  static String  SubString(String htmlCode) {
         
// htmlCode = " <span style=\"font-size: small\"><span style=\"font-family: 楷体\">雨过白鹭州<br /></span></span> ";

htmlCode = new String(subStringHTML(htmlCode,200));
//System.out.println(htmlCode);
                 return htmlCode;
           
  }
/**public static void main(String[] args) {
String htmlCode = " <span style=\"font-size: small\"><span style=\"font-family: 楷体\">雨过白鹭州<br /></span></span> ";
System.out.println(subStringHTML(htmlCode,2));

}

* 按子节长度截取字符串(支持截取带HTML代码样式的字符串)<br>
* 如：<span>中国人发在线</span> 当截取2个字节得到的结果是：<span>中国
* 
* @param param
*            将要截取的含html代码的字符串参数
* @param length
*            截取的字节长度
* @return 返回截取后的字符串
* @author YangJunping
* @date 2010-7-15
*/
public static String subStringHTML(String param, int length) {
StringBuffer result = new StringBuffer();
int n = 0;
char temp;
boolean isCode = false; // 是不是HTML代码
boolean isHTML = false; // 是不是HTML特殊字符,如&nbsp;
for(int i = 0; i < param.length(); i++) {
temp = param.charAt(i);
if(temp == '<') {
isCode = true;
}else if(temp == '&') {
isHTML = true;
}else if(temp == '>' && isCode) {
n = n - 1;
isCode = false;
}else if(temp == ';' && isHTML) {
isHTML = false;
}
if(!isCode && !isHTML) {
n = n + 1;
// UNICODE码字符占两个字节
if((temp + "").getBytes().length > 1) {
n = n + 1;
}
}
result.append(temp);
if(n >= length) {
break;
}
}
return fix(result.toString());
}
/**
* 补全HTML代码<br>
* 如：<span>中国 ---> <span>中国</span>
* 
* @param str
* @return
* @author YangJunping
* @date 2010-7-15
*/
private static String fix(String str) {
StringBuffer fixed = new StringBuffer(); // 存放修复后的字符串
TagsList[] unclosedTags = getUnclosedTags(str);
// 生成新字符串
for(int i = unclosedTags[0].size() - 1; i > -1; i--) {
fixed.append("<" + unclosedTags[0].get(i) + ">");
}
fixed.append(str);
for(int i = unclosedTags[1].size() - 1; i > -1; i--) {
String s = null;
if((s = unclosedTags[1].get(i)) != null) {
fixed.append("</" + s + ">");
}
}
return fixed.toString();
}
private static TagsList[] getUnclosedTags(String str) {
StringBuffer temp = new StringBuffer(); // 存放标签
TagsList[] unclosedTags = new TagsList[2];
unclosedTags[0] = new TagsList(); // 前不闭合，如有</div>而前面没有<div>
unclosedTags[1] = new TagsList(); // 后不闭合，如有<div>而后面没有</div>
boolean flag = false; // 记录双引号"或单引号'
char currentJump = ' '; // 记录需要跳过''还是""
char current = ' ', last = ' '; // 当前 & 上一个
// 开始判断
for(int i = 0; i < str.length();) {
current = str.charAt(i++); // 读取一个字符
if(current == '"' || current == '/') {
flag = flag ? false : true; // 若为引号，flag翻转
currentJump = current;
}
if(!flag) {
if(current == '<') { // 开始提取标签
current = str.charAt(i++);
if(current == '/') { // 标签的闭合部分，如</div>
current = str.charAt(i++);
// 读取标签
while(i < str.length() && current != '>') {
temp.append(current);
current = str.charAt(i++);
}
// 从tags_bottom移除一个闭合的标签
if(!unclosedTags[1].remove(temp.toString())) { // 若移除失败，说明前面没有需要闭合的标签
unclosedTags[0].add(temp.toString()); // 此标签需要前闭合
}
temp.delete(0, temp.length()); // 清空temp
}else { // 标签的前部分，如<div>
last = current;
while(i < str.length() && current != ' ' && current != ' ' && current != '>') {
temp.append(current);
last = current;
current = str.charAt(i++);
}
// 已经读取到标签，跳过其他内容，如<div id=test>跳过id=test
while(i < str.length() && current != '>') {
last = current;
current = str.charAt(i++);
if(current == '"' || current == '/') { // 判断引号
flag = flag ? false : true;
currentJump = current;
if(flag) { // 若引号不闭合，跳过到下一个引号之间的内容
while(i < str.length() && str.charAt(i++) != currentJump)
;
current = str.charAt(i++);
flag = false;
}
}
}
if(last != '/' && current == '>') // 判断这种类型：<TagName />
unclosedTags[1].add(temp.toString());
temp.delete(0, temp.length());
}
}
}else {
while(i < str.length() && str.charAt(i++) != currentJump)
; // 跳过引号之间的部分
flag = false;
}
}
return unclosedTags;
}
}

package com.tools;


public class TagsList {
private String[] data;
private int size = 0;
public TagsList(int size) {
data = new String[size];
}
public TagsList() {
this(10);
}
public void add(String str) {
ensureCapacity(size + 1);
data[size++] = str;
}
public String get(int index) {
if(index < size)
return data[index];
else
return null;
}
// 为了提高效率，只将其置为null
public boolean remove(String str) {
for(int index = 0; index < size; index++) {
if(str.equals(data[index])) {
data[index] = null;
return true;
}
}
return false;
}
public boolean remove(int index) {
if(index < data.length) {
data[index] = null;
return true;
}
return false;
}
public int size() {
return this.size;
}
// 扩展容量
public void ensureCapacity(int minSize) {
int oldCapacity = data.length;
if(minSize > oldCapacity) {
int newCapacity = (oldCapacity * 3 / 2 + 1) > minSize ? oldCapacity * 3 / 2 + 1 : minSize;
String[] newArray = new String[newCapacity];
for(int i = 0; i < data.length; i++) {
newArray[i] = data[i];
}
data = newArray;
}
}
}