我正在尝试使用XML规则中不允许的字符捕获ValidationEvent
。 (例如,“&”)
另外,我设置了ValidationEventHandler
来检查非编组错误。 我尝试使用InputStream
进行解组,但是事件处理程序无法捕获错误。 handleEvent
方法根本没有执行。另一方面,使用StringReader
可以正常使用。
我已经阅读了描述unmarshal
方法的Javadoc。但是,我没有看到它无法捕获ValidationEvent。
从指定的InputStream解组XML数据,并返回结果内容树。使用这种形式的解组API时,验证事件位置信息可能不完整。
在最后一次尝试中,我确实尝试过在线搜索,但找不到任何东西。
任何帮助将不胜感激:D
很抱歉添加一个问题。 (POJO类已经改变了一点……)
我用与XML元素名称不同的@XmlPath
注释定义了 POJO类字段,但似乎不起作用。我应该将其用作XmlElement吗?
import org.eclipse.persistence.oxm.annotations.XmlPath;
import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
import java.util.List;
@XmlRootElement
class Article {
private String title;
private String category;
private List<ArticleImage> imageList;
public String getTitle() {
return title;
}
@XmlElement
public void setTitle(String title) {
this.title = title;
}
public String getCategory() {
return category;
}
@XmlElement
public void setCategory(String category) {
this.category = category;
}
public List<ArticleImage> getImageList() {
return imageList;
}
// for Extra Question... :D
@XmlPath("image")
public void setImageList(List<ArticleImage> imageList) {
this.imageList = imageList;
}
}
class ArticleImage {
private String url;
private String ext;
public String getUrl() {
return url;
}
@XmlAttribute
public void setUrl(String url) {
this.url = url;
}
public String getExt() {
return ext;
}
@XmlAttribute
public void setExt(String ext) {
this.ext = ext;
}
}
import javax.xml.bind.ValidationEvent;
import javax.xml.bind.ValidationEventHandler;
import javax.xml.bind.ValidationEventLocator;
class CustomValidationHandler implements ValidationEventHandler {
// This method is not reached when debugging.
@Override
public boolean handleEvent(ValidationEvent event) {
if (event.getSeverity() == ValidationEvent.FATAL_ERROR ||
event.getSeverity() == ValidationEvent.ERROR) {
ValidationEventLocator locator = event.getLocator();
throw new RuntimeException("Error in EventHandler. line number: " + locator.getLineNumber());
}
return true;
}
}
import org.eclipse.persistence.jaxb.JAXBContextFactory;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.Unmarshaller;
import java.io.ByteArrayInputStream;
import java.io.InputStream;
public class SomeTest {
public void someMethod() {
String xmlString = "<article type=\"item\">\n"
+ " <title>M&A</title>\n"
+ " <category>1234-1234</category>\n"
+ " <image url=\"hello\" ext=\"jpg\"/>\n"
+ "</article>";
try (InputStream fileInputStream = new ByteArrayInputStream(xmlString.getBytes())) {
JAXBContext context = JAXBContextFactory.createContext(new Class[]{Article.class}, null);
Unmarshaller unmarshaller = context.createUnmarshaller();
unmarshaller.setEventHandler(new CustomValidationHandler());
Article article = (Article) unmarshaller.unmarshal(fileInputStream);
System.out.println(article.getTitle());
} catch (Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
new SomeTest().someMethod();
}
}
答案 0 :(得分:9)
最初建议替换
JAXBContext context = JAXBContextFactory.createContext(new Class[]{Article.class}, null);
到
JAXBContext context = JAXBContext.newInstance(Article.class);
在JAXBContextFactory.createContext的实现中,您可以看到对您通过了Article的classesToBeBound进行了一些检查,这些检查导致“无法找到要委托的JAXB实现”的异常。这是我在运行代码时遇到的问题,我认为您也有。然后调用了事件处理程序(至少在我的设置中如此)。
稍后您遇到“ ...类的问题,该类具有两个相同名称的“ value” ...”属性,我建议检查此链接,以解释发生这种情况的原因。
链接为:What is the difference between using @XmlElement before field and before getter declaration?
编辑以回答新问题:
如果您不介意我问您要如何使用@XmlPath("image")
?
您的POJO结构与xml不匹配。删除注释并更改图像的设置方法,如下所示:
@XmlRootElement
class Article {
private String title;
private String category;
private List<ArticleImage> imageList;
public String getTitle() {
return title;
}
@XmlElement
public void setTitle(String title) {
this.title = title;
}
public String getCategory() {
return category;
}
@XmlElement
public void setCategory(String category) {
this.category = category;
}
public List<ArticleImage> getImage() {
return imageList;
}
// for Extra Question... :D
// method name changed!
public void setImage(List<ArticleImage> imageList) {
this.imageList = imageList;
}
}
class ArticleImage {
private String url;
private String ext;
public String getUrl() {
return url;
}
@XmlAttribute
public void setUrl(String url) {
this.url = url;
}
public String getExt() {
return ext;
}
@XmlAttribute
public void setExt(String ext) {
this.ext = ext;
}
}
答案 1 :(得分:1)
在两种情况下均有效: InputStream 和 StringReader
只是更改为:
JAXBContext context = JAXBContext.newInstance(Article.class);
答案 2 :(得分:0)
如@mart和@Sergey所述
更新JAXBContext context = JAXBContextFactory.createContext(new Class [] {Article.class},null);
JAXBContext context = JAXBContext.newInstance(Article.class);
还添加 @XmlAccessorType(XmlAccessType.FIELD)在您的Article pojo类中。
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
@XmlRootElement
@XmlAccessorType(XmlAccessType.FIELD)
public class Article {
@XmlElement
private String title;
@XmlElement
private String category;
//setter getters
}
我检查了它,如果发生异常,则调用CustomValidationHandler。