java xpath demo

package com.maomao.xpath.test; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import com.maomao.xpath.utils.XPathUtils; public class PredicatesTest { private static final String RES = "resource/predicatesTest.xml"; public static void main(String[] args) { queryTheTitleOfFirstBook(); queryBookNameOfLastOne(); queryBookNameOfLastSecondOne(); queryBookNameOfBeforTwo(); queryBookNameOfWhosePriceMoreThanfifity(); queryNodeHasAttribute(); queryBookAttributeIsCN(); queryAllNode(); queryTitleAndPrice(); } /** * 获取第一本书的名字 */ private static void queryTheTitleOfFirstBook() { NodeList result = XPathUtils.queryNodelist(RES, "/bookstore/book[1]/title"); System.out.println("***********************查询第一本书的名称**************************"); printInfo(result); } /** * 获取最后一本书的书名 */ private static void queryBookNameOfLastSecondOne() { NodeList result = XPathUtils.queryNodelist(RES, "/bookstore/book[last()]/title"); System.out.println("**********************查询最后一本书的名称*************************"); printInfo(result); } /** * 获取倒数第二本书的名字 */ private static void queryBookNameOfLastOne() { NodeList result = XPathUtils.queryNodelist(RES, "/bookstore/book[last()-1]/title"); System.out.println("**********************查询倒数第二本书的名称*************************"); printInfo(result); } /** * 查询前面两本书的书名 * */ private static void queryBookNameOfBeforTwo() { NodeList result = XPathUtils.queryNodelist(RES, "/bookstore/book[position()<3]/title"); System.out.println("**********************查询前面两本书的书名*************************"); printInfo(result); } /** * 查询价格大于50的书籍 */ private static void queryBookNameOfWhosePriceMoreThanfifity() { NodeList result = XPathUtils.queryNodelist(RES, "/bookstore/book[price>50.0]/title"); System.out.println("**********************查询价格大于50的书籍*************************"); printInfo(result); } /** * 选取所有带有属性的 title 元素。 */ private static void queryNodeHasAttribute() { NodeList result = XPathUtils.queryNodelist(RES, "//title[@*]"); System.out.println("**********************选取所有带有属性的 title 元素*************************"); printInfo(result); } /** * 选取所有中文书的价格 */ private static void queryBookAttributeIsCN() { NodeList result = XPathUtils.queryNodelist(RES, "/bookstore/book[title[@lang='cn']]/price"); System.out.println("**********************选取所有中文书的价格*************************"); printInfo(result); } /** * 选取所有节点 */ private static void queryAllNode() { NodeList result = XPathUtils.queryNodelist(RES, "//*"); System.out.println("**********************选取所有文档节点*************************"); printInfo(result); } /** * 选取所有书的书名和价格 */ private static void queryTitleAndPrice() { NodeList result = XPathUtils.queryNodelist(RES, "//book/title|//book/price"); System.out.println("**********************选取所有书的书名和价格*************************"); printInfo(result); } private static void printInfo(NodeList result) { System.out.println("查询结果："); System.out.println("查询到的 (" + result.getLength() + ") 个节点。"); for (int i = 0; i < result.getLength(); i++) { Node node = result.item(i); String nodeName = node.getNodeName(); String text = node.getTextContent(); System.out.println(nodeName + " --> " + text); } System.out.println("*****************************************************************\r\n\r\n"); } }