使用XSD验证XML

本文简单介绍如何使用XSD验证自己的xml。项目中我们经常使用xml作为配置或者数据交互的文件格式，在解析XML前最好验证一下或者在生成xml文件后验证一下生成的文件格式是正确，这样可以避免解析时出现一些低级的xml文件不符合预定义格式的错误。

CSDN无法正确显示这些xsd， xml以及java代码，如果需要请参考 http://yqbjtu.blog.163.com/blog/static/529426201672674444341/
第一步显示定义XSD，这个参考网上很多教程，本文给出一个简单实例。

order_v1.xsd

<?xml version="1.0" encoding="UTF-8"?>
- Licensed Text
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
        elementFormDefault="qualified"
        targetNamespace="http://demo.com/OrderXMLSchema_v1"
        xmlns:tns="http://demo.com/OrderXMLSchema_v1">
<xsd:element name="shipOrder" type="tns:shipOrder"></xsd:element>
  <xsd:complexType name="shipOrder">
    <xsd:sequence maxOccurs="1" minOccurs="1">
        <xsd:element name="orderperson" type="xsd:string" minOccurs="1" maxOccurs="1"></xsd:element>
        <xsd:element name="order-description" type="xsd:string" minOccurs="1" maxOccurs="1"></xsd:element>
        <xsd:element name="items" type="tns:items" maxOccurs="1" minOccurs="1"></xsd:element>
        <xsd:element name="item-2" type="tns:item-2" maxOccurs="unbounded" minOccurs="1"></xsd:element>
    </xsd:sequence>
  </xsd:complexType>
  <xsd:complexType name="items">
      <xsd:sequence maxOccurs="unbounded" minOccurs="1">
        <xsd:element name="item" minOccurs="1" maxOccurs="1">
          <xsd:complexType>
            <xsd:simpleContent>
                <xsd:extension base="xsd:string">
                  <xsd:attribute name="index" type="xsd:unsignedLong" />
                </xsd:extension>
            </xsd:simpleContent>
          </xsd:complexType>
        </xsd:element>
      </xsd:sequence>
  </xsd:complexType>
  <xsd:complexType name="item-2">
      <xsd:sequence maxOccurs="1" minOccurs="1">
          <xsd:element name="title" type="xsd:string"/>
          <xsd:element name="note" type="xsd:string" minOccurs="0"/>
          <xsd:element name="quantity" type="xsd:positiveInteger"/>
          <xsd:element name="price" type="xsd:decimal"/>
      </xsd:sequence>
      <xsd:attribute name="index" type="xsd:unsignedLong" />
  </xsd:complexType>
</xsd:schema>

Xml文件

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
- Licensed Description.
<shipOrder xmlns="http://demo.com/OrderXMLSchema_v1"
   xmlns:server="http://demo.com/OrderXMLSchema_v1"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <orderperson>John Smith</orderperson>
  <order-description>This document is used for demo sxN#</order-description>
  <items>
      <item index="1">
        some potatoes
      </item>
      <item index="2">
        some tomatoes
      </item>
  </items>
      <item-2 index="1">
            <title>Hide your heart</title>
            <quantity>1</quantity>
            <price>9.90</price>
      </item-2>
      <item-2 index="2">
            <title>Hide your heart</title>
            <note>this is for testing note, it is not required</note>
            <quantity>1</quantity>
            <price>9.90</price>
      </item-2>
</shipOrder>

最后是我们的java代码

import java.io.File;
import java.io.UnsupportedEncodingException;
import javax.xml.transform.Source;
import javax.xml.transform.stream.StreamSource;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;
import javax.xml.validation.Validator;
import org.xml.sax.SAXException;
public class index="2">
            <title>Hide your heart</title>
            <note>this is for testing note, it is not required</note>
            <quantity>1</quantity>
            <price>9.90</price>
      </item-2>

其余部分基本类似，比较需要注意的是item类型，它有attribute也有value。

 <item index="2"> some tomatoes </item>

它的定义是

        <xsd:element name="item" minOccurs="1" maxOccurs="1">
          <xsd:complexType>
            <xsd:simpleContent>
                <xsd:extension base="xsd:string">
                  <xsd:attribute name="index" type="xsd:unsignedLong" />
                </xsd:extension>
            </xsd:simpleContent>
          </xsd:complexType>
        </xsd:element>