java.lang.NumberFormatException

相关截图：

//问题描述：XmlDataSource.java第57行如下所示，XmlDataSource.java完整代码附加在其后
//painting.setCategory(Integer.parseInt(element.elementText("category")));

package com.imooc.mgallery.utils;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
import java.io.Writer;
import java.net.URLDecoder;
import java.util.ArrayList;
import java.util.List;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.Node;
import org.dom4j.io.SAXReader;

import com.imooc.mgallery.entity.Painting;

/**
 * 
 * 数据源类，用于将XML文件解析为Java对象
 *
 */
public class XmlDataSource {
	// 通过static关键字来保证数据全局唯一
	private static List<Painting> data = new ArrayList();
	private static String dataFile;
	static {
		// 得到painting.xml文件完整物理路径 
		// c:\new style\painting.xml
		// c:\new%20style\painting.xml
		dataFile = XmlDataSource.class.getResource("/painting.xml").getPath();
		reload();

	}

	private static void reload() {
		URLDecoder decoder = new URLDecoder();
		try {
			decoder.decode(dataFile, "UTF-8");
			System.out.println(dataFile);
			// 利用Dom4j对XML进行解析
			SAXReader reader = new SAXReader();
			// 1. 获取Document文档对象
			Document document = reader.read(dataFile);
			// 2.Xpath得到XML节点集合
			List<Node> nodes = document.selectNodes("/root/painting");
			data.clear();
			for (Node node : nodes) {
				Element element = (Element) node;
				String id = element.attributeValue("id");
				String pname = element.elementText("pname");
				Painting painting = new Painting();
				painting.setId(Integer.parseInt(id));
				painting.setPname(pname);
				painting.setCategory(Integer.parseInt(element.elementText("category")));
				painting.setPrice(Integer.parseInt(element.elementText("price")));
				painting.setPreview(element.elementText("preview"));
				painting.setDescription(element.elementText("description"));
				data.add(painting);
//				System.out.println(id+":" + pname);
			}

		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

	/**
	 * 获取所有Painting对象
	 * @return Painting List
	 */
	public static List<Painting> getRawPainting() {
		return data;
	}
	public static void append(Painting painting) {
		//1.读取XML文档，得到document对象
		SAXReader reader = new SAXReader();
		Writer writer = null;
		try {
			Document document = reader.read(dataFile);
			//2.创建新的painting节点
			 Element root = document.getRootElement();//<root>
			 Element p = root.addElement("painting");
			//3.创建painting节点的各个子节点
			 p.addAttribute("id", String.valueOf(data.size()+1));
			 p.addElement("pname").setText(painting.getPname());
			 p.addElement("category").setText(painting.getCategory().toString());
			 p.addElement("price").setText(painting.getPrice().toString());
			 p.addElement("preview").setText(painting.getPreview());
			 p.addElement("description").setText(painting.getDescription());
			//4.写入XML，完成追加操作
			 writer = new OutputStreamWriter(new FileOutputStream(dataFile),"UTF-8");
			 document.write(writer);
			 System.out.println(dataFile);
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally {
			if(writer != null) {
				try {
					writer.close();
				} catch (Exception e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
			reload();//内存与文件数据一致
		}

	}

	public static void main(String[] argn) {
//		new XmlDataSource();
//		List<Painting> ps = XmlDataSource.getRawPainting();
//		System.out.println(ps);

		Painting p = new Painting();
		p.setPname("测试油画");
		p.setCategory(1);
		p.setPrice(12000);
		p.setPreview("/upload/10.jpg");
		p.setDescription("测试油画描述");
		XmlDataSource.append(p);
	}
}