JSoup快速入门-java解析html源码

安装-运行时依赖关系

<dependency>
  <!-- jsoup HTML parser library @ http://jsoup.org/ -->
  <groupId>org.jsoup</groupId>
  <artifactId>jsoup</artifactId>
  <version>1.10.2</version>
</dependency>

1. 载入文件

从URL加载文档，使用Jsoup.connect()方法从URL加载HTML。

try
{
    Document document = Jsoup.connect("http://www.yiibai.com").get();
    System.out.println(document.title());
} 
catch (IOException e) 
{
    e.printStackTrace();
}

2. 从文件加载文档

使用Jsoup.parse()方法从文件加载HTML。

{
    Document document = Jsoup.parse( new File( "D:/temp/index.html" ) , "utf-8" );
    System.out.println(document.title());
} 
catch (IOException e) 
{
    e.printStackTrace();
}

3. 从String加载文档

使用Jsoup.parse()方法从字符串加载HTML。

try
{
    String html = "<html><head><title>First parse</title></head>"
                    + "<body><p>Parsed HTML into a doc.</p></body></html>";
    Document document = Jsoup.parse(html);
    System.out.println(document.title());
} 
catch (IOException e) 
{
    e.printStackTrace();
}

4. 在HTML页面中获取表单属性

在网页中获取表单输入元素非常简单。使用唯一ID查找FORM元素; 然后找到该表单中存在的所有INPUT元素。

Document doc = Jsoup.parse(new File("c:/temp/yiibai-index.html"),"utf-8");  
Element formElement = doc.getElementById("loginForm");  
 
Elements inputElements = formElement.getElementsByTag("input");  
for (Element inputElement : inputElements) {  
    String key = inputElement.attr("name");  
    String value = inputElement.attr("value");  
    System.out.println("Param name: "+key+" \nParam value: "+value);  
}

5.获取URL的元信息

元信息包括Google等搜索引擎用来确定网页内容的索引为目的。它们以HTML页面的HEAD部分中的一些标签的形式存在。要获取有关网页的元信息，请使用下面的代码。

try
{
    Document document = Jsoup.parse(new File("C:/Users/zkpkhua/Desktop/yiibai-index.html"), "utf-8");
 
    String description = document.select("meta[name=description]").get(0).attr("content");  
    System.out.println("Meta description : " + description);  
 
    String keywords = document.select("meta[name=keywords]").first().attr("content");  
    System.out.println("Meta keyword : " + keywords);  
} 
catch (IOException e) 
{
    e.printStackTrace();
}

Httpclient

https://www.cnblogs.com/bingyimeiling/p/11820583.html

json序列化返回金额两位数

public class DataSerializerUtils extends JsonSerializer<BigDecimal> {


    @Override
    public void serialize(BigDecimal value, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException {
        if(value!=null && !"".equals(value)) {
            jsonGenerator.writeString(value.setScale(2,BigDecimal.ROUND_HALF_DOWN)+"");
        }else {
            jsonGenerator.writeString(value+"");
        }
    }
}
在具体字段上加注解即可
    @ApiModelProperty(value = "支付金额", name = "payAmount")
    @JsonSerialize(using = DataSerializerUtils.class)
    private BigDecimal payAmount;

springboot|springmvc文件下载

@RequestMapping(value = "downPhotoById")  
public void downPhotoByStudentId(String id, final HttpServletResponse response){  
    PhotoEntity entity = this.photoMapper.getPhotoEntityByPhotoId(id);  
    byte[] data = entity.getPhotoData();  
    String fileName = entity.getFileName()== null ? "照片.png" : entity.getFileName();  
    fileName = URLEncoder.encode(fileName, "UTF-8");  
    response.reset();  
    response.setHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");  
    response.addHeader("Content-Length", "" + data.length);  
    response.setContentType("application/octet-stream;charset=UTF-8");  
    OutputStream outputStream = new BufferedOutputStream(response.getOutputStream());  
    outputStream.write(data);  
    outputStream.flush();  
    outputStream.close();  
}

两个时间之间的相差秒数，小时

Duration duration = Duration.between(payOrderDO.getCreateTime().toInstant().atZone( ZoneId.systemDefault() ).toLocalDateTime(), LocalDateTime.now());
    long days = duration.toDays();
    long hours = duration.toHours();
    long millis = duration.toMillis()/1000;

2020-01-18周总结