插件工具 - Jsoup学习

插件工具 - Jsoup学习"/>

插件工具 - Jsoup学习

建筑的永恒之道

囫囵吞枣地看完了这本书，体会到了一些东西，开始感受无名特质：生气，完整，舒适，自由，准确，无我，永恒。

希望能在软件设计的过程中发现好的模式，顺应模式，忘却模式，创造模式。遵循道却不囿于道。

html解析器

1. 从一个url、文件或字符串中解析html；
2. 使用dom或css来查找、取出数据；
3. 可操作html元素、属性、文本；

        /*** 根据属性选择*/public class JsoupDemo02 {public static void main(String[] args) throws Exception{//新建HttpClientCloseableHttpClient httpClient = HttpClients.createDefault();HttpGet httpGet = new HttpGet("/");//返回响应CloseableHttpResponse response = null;//执行请求try {response = httpClient.execute(httpGet);//获取实体HttpEntity entity = response.getEntity();//获取内容String content = EntityUtils.toString(entity,"utf-8");//获取Dom元素Document document = Jsoup.parse(content);//获取tag为标题的元素Elements elementsByTag = document.getElementsByTag("title");//打印标题内容System.out.println("网页第一个标题: "+elementsByTag.get(0).text());//获取网页id为site_nav_top的文档对象Element elementById = document.getElementById("site_nav_top");//打印该id对应的内容System.out.println("id为site_nav_top的内容:"+elementById.html());//获取class为post_item的元素Elements elementsByClass = document.getElementsByClass("post_item");for (Element element : elementsByClass) {System.out.println("class属性为post_item: " + element.html());}//获取属性是height的元素Elements elementsByAttribute = document.getElementsByAttribute("height");for (Element element : elementsByAttribute) {System.out.println("属性为height: " + element.toString());}//获取属性target的值为_blank的元素Elements elementsByAttributeValue = document.getElementsByAttributeValue("target", "_blank");for (Element element : elementsByAttributeValue) {System.out.println("属性target的值为_blank: "+ element.toString());}} catch (ClientProtocolException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} finally {//关闭资源if (response != null) {try {response.close();} catch (IOException e) {e.printStackTrace();}}}//关闭资源httpClient.close();}}/*** 根据选择器选择*/public class JsoupDemo03 {public static void main(String[] args) throws Exception{//新建HttpClientCloseableHttpClient httpClient = HttpClients.createDefault();HttpGet httpGet = new HttpGet("/");//返回响应CloseableHttpResponse response = null;//执行请求try {response = httpClient.execute(httpGet);//获取实体HttpEntity entity = response.getEntity();//获取内容String content = EntityUtils.toString(entity,"utf-8");//获取Dom元素Document document = Jsoup.parse(content);//使用id选择器Elements selectElements = document.select("#post_list .post_item .post_item_body h3 a");for (Element element : selectElements) {System.out.println("标题: "+element.text());System.out.println("博客地址: " + element.attr("href"));System.out.println("target: " + element.attr("target"));}System.out.println("------------");//选择带有href属性的a标签元素Elements hrefElements = document.select("a[href]");for (Element element : hrefElements) {System.out.println("a标签的链接: "+element.toString());}//选择扩展名为.png的图片Elements imgElements = document.select("img[src$=.png]");for (Element element : imgElements) {System.out.println("图片: " + element.toString() );}//获取第一个标题Element title = document.getElementsByTag("title").first();System.out.println("网页标题: " + title.text());} catch (ClientProtocolException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} finally {//关闭资源if (response != null) {try {response.close();} catch (IOException e) {e.printStackTrace();}}}//关闭资源httpClient.close();}}