在我的环境中，我使用Java将结果集序列化为XML。
它基本上是这样的：

//foreach column of each row
xmlHandler.startElement(uri, lname, "column", attributes);
String chars = rs.getString(i);
xmlHandler.characters(chars.toCharArray(), 0, chars.length());
xmlHandler.endElement(uri, lname, "column");

XML在Firefox中如下所示：

<row num="69004">
    <column num="1">10069</column>
    <column num="2">sd&#26;</column>
    <column num="3">FCVolume                      </column>
</row>

但是，当我解析XML时，我得到了一个

org.xml.sax.SAXParseException: Character reference "&#26" is an
  invalid XML character.

现在我的问题是：我必须替换哪些字符，或者如何编码我的字符，以使它们成为有效的XML？

解决方案

可扩展标记语言(XML)1.0说：

The ampersand character (&) and the
  left angle bracket (<) must not appear
  in their literal form, except when
  used as markup delimiters, or within a
  comment, a processing instruction, or
  a CDATA section. If they are needed
  elsewhere, they must be escaped using
  either numeric character references or
  the strings "&" and "<"
  respectively. The right angle bracket
  (>) may be represented using the
  string ">", and must, for
  compatibility, be escaped using either
  ">" or a character reference when
  it appears in the string "]]>" in
  content, when that string is not
  marking the end of a CDATA section.

如果使用CDATA，则可以跳过编码：

<column num="1"><![CDATA[10069]]></column>
<column num="2"><![CDATA[sd&]]></column>

我在Xml Spec中找到了一个有趣的列表：
根据该列表，不鼓励使用字符＃26(十六进制：＃x1A)。

The characters defined in the
  following ranges are also discouraged.
  They are either control characters or
  permanently undefined Unicode
  characters

查看完整范围。

此代码从字符串中替换所有无效的Xml Utf8：

public String stripNonValidXMLCharacters(String in) {
    StringBuffer out = new StringBuffer(); // Used to hold the output.
    char current; // Used to reference the current character.

    if (in == null || ("".equals(in))) return ""; // vacancy test.
    for (int i = 0; i < in.length(); i++) {
        current = in.charAt(i);
        if ((current == 0x9) ||
            (current == 0xA) ||
            (current == 0xD) ||
            ((current >= 0x20) && (current <= 0xD7FF)) ||
            ((current >= 0xE000) && (current <= 0xFFFD)) ||
            ((current >= 0x10000) && (current <= 0x10FFFF)))
            out.append(current);
    }
    return out.toString();
}

它取自无效的XML字符：当有效的UTF8并不意味着有效的XML时

但是与此同时，我仍然遇到UTF-8兼容性问题：

org.xml.sax.SAXParseException: Invalid byte 1 of 1-byte UTF-8 sequence

从servlet读取XML并将XML返回为UTF-8的XML后，我只是尝试了将Contenttype设置为以下情况会发生的情况：

response.setContentType("text/xml;charset=utf-8");

它奏效了....

我们正在运行哪个版本的JRE？萨克斯项目说：

J2SE 1.4 bundles an old version of
  SAX2. How do I make SAX2 r2 or later available?