使用Apache的Digester解析XML文件

happy_boy

　　物采系统中，读取*query*.xml文件，使用了Apache的Digester来解析，我做的专家信息导入模块，也需要读取定义在XMl中的导入验证规则。原来使用的是ShiChao提供的SAX解析XML文件方法。现在改为用Digester来解析。
　　使用的是org.apache.commons.digester3.annotations下的包，annotations顾名思义就是注释模式，可参照：
　　http://commons.apache.org/digester/guide/annotations.html 上的样例。
　　我的做法具体如下：
　　1.我的导入规则验证的XML文件的内容:

<?xml version="1.0" encoding="UTF-8"?>
<validators>
<header name="出生日期">
<validator type="reg">
<reg>^\d{4}[\/-]\d{1,2}[\/-]\d{1,2}$</reg>
</validator>
</header>
<header name="身份证*">
<validator type="reg">
<reg>^(\d{17})(\d|[xX])$</reg>
</validator>
<validator type="uniq">
<className>com.cnpc.pms.exp.inf.entity.ExpertInfo</className>
<filedName>idCardNum</filedName>
</validator>
</header>
<header name="推荐单位*">
<validator type="refer">
<className>com.cnpc.pms.bizbase.rbac.orgview.entity.PurStruOrg</className>
<filedName>code</filedName>
</validator>
</header>
<header name="评审专业*">
<validator type="custom">
<className>expImportExcelManager</className>
<methodName>verifyCategory</methodName>
</validator>
</header>
..................
</validators>

　　2.由于使用的是Digester的annotations模式，所以需要建立几个与xml文件内容相互映射的java bean：
　　  (1).ExpImpValContext类：

package com.cnpc.pms.exp.inf.dto;
import java.util.ArrayList;
import java.util.List;
import org.apache.commons.digester.annotations.rules.ObjectCreate;
import org.apache.commons.digester.annotations.rules.SetNext;
import com.cnpc.pms.base.query.model.PMSQuery;
/**
* @author Song Shitao
* @since 2011/7/11
*/
@ObjectCreate(pattern = "validators")
public class ExpImpValContext {
/** The queries. */
private List<ExpImpValHeader> headers = new ArrayList<ExpImpValHeader>();
/**
* Adds the header.
*
* @param header
*            the header
*/
@SetNext
public void addHeader(ExpImpValHeader header) {
this.headers.add(header);
}
/**
* Gets the headers.
*
* @return the headers
*/
public List<ExpImpValHeader> getHeaders() {
return headers;
}
}

　　(2).ExpImpValHeader类：

package com.cnpc.pms.exp.inf.dto;
import java.util.ArrayList;
import java.util.List;
import org.apache.commons.digester.annotations.rules.ObjectCreate;
import org.apache.commons.digester.annotations.rules.SetNext;
import org.apache.commons.digester.annotations.rules.SetProperty;
/**
* @author Song Shitao
* @since 2011/7/11
*/
@ObjectCreate(pattern = "validators/header")
public class ExpImpValHeader {
/** The name. */
@SetProperty(attributeName = "name", pattern = "validators/header")
private String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
/** The validators. */
private List<ExpImpValidator> validators = new ArrayList<ExpImpValidator>();
/**
* Adds the validator.
*
* @param validator
*            the validator
*/
@SetNext
public void addValidator(ExpImpValidator validator) {
this.validators.add(validator);
}
/**
* Gets the validators.
*
* @return the validators
*/
public List<ExpImpValidator> getValidators() {
return validators;
}
}

　　(3).ExpImpValidator类:

package com.cnpc.pms.exp.inf.dto;
import org.apache.commons.digester.annotations.rules.BeanPropertySetter;
import org.apache.commons.digester.annotations.rules.ObjectCreate;
import org.apache.commons.digester.annotations.rules.SetProperty;
/**
* @author Song Shitao
* @since 2011/7/11
*/
@ObjectCreate(pattern = "validators/header/validator")
public class ExpImpValidator {
/** The type. */
@SetProperty(attributeName = "type", pattern = "validators/header/validator")
private String type;
@BeanPropertySetter( pattern = "validators/header/validator/className" )   
private String className;
@BeanPropertySetter( pattern = "validators/header/validator/filedName" )   
private String filedName;
@BeanPropertySetter( pattern = "validators/header/validator/methodName" )   
private String methodName;
@BeanPropertySetter( pattern = "validators/header/validator/reg" )   
private String reg;
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
public String getClassName() {
return className;
}
public void setClassName(String className) {
this.className = className;
}
public String getFiledName() {
return filedName;
}
public void setFiledName(String filedName) {
this.filedName = filedName;
}
public String getMethodName() {
return methodName;
}
public void setMethodName(String methodName) {
this.methodName = methodName;
}
public String getReg() {
return reg;
}
public void setReg(String reg) {
this.reg = reg;
}
}

　　注：可以看到在java类里出现了@SetProperty标签和@BeanPropertySetter标签，前者对应的是形如：
　　<id value="abc" />这样的映射，后者对应的是形如:<id>abc</id>这样的映射。
　　3.在main函数中启动：

package com.cnpc.pms.exp.inf.dto;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
import org.apache.commons.digester.Digester;
import org.apache.commons.digester.annotations.DigesterLoader;
import org.apache.commons.digester.annotations.DigesterLoaderBuilder;
import org.springframework.core.io.Resource;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import com.cnpc.pms.base.util.ConfigurationUtil;
public class Index {
public static final String DEFAULT_CONFIG_LOCATION = "/conf/expinfo-import-validate-rules.xml";
public static void main(String[] args) {
Resource[] resources = ConfigurationUtil
.getAllResources(DEFAULT_CONFIG_LOCATION);
if (resources != null) {
for (int i = 0; i < resources.length; i++) {
Resource resource = resources;
try {
ExpImpValContext expImpValContext = parseXMLObject(ExpImpValContext.class, resource);
List<ExpImpValHeader> list = expImpValContext.getHeaders();
list.iterator();
} catch (IOException e) {
} catch (SAXException e) {
}
}
}
}
public static <T> T parseXMLObject(Class<T> clazz, Resource resource) throws IOException, SAXException {
InputStream is = resource.getInputStream();
InputSource inputSource = new InputSource(is);
DigesterLoader digesterLoader =
new DigesterLoaderBuilder().useDefaultAnnotationRuleProviderFactory()
.useDefaultDigesterLoaderHandlerFactory();
Digester digester = digesterLoader.createDigester(clazz);
return (T) digester.parse(inputSource);
}
}