看之前要先对SpringMVC进行了解打好基础，下面直接先看效果图
代码编写
1.导入相关架包
2.配置文件
web.xml
<?xml version="1.0" encoding="UTF-8"?><web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1"> <display-name>watermarkspringmvc</display-name> <servlet> <servlet-name>dispatcherServlet</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:springmvc.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>dispatcherServlet</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list></web-app>
springmvc.xml
<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd"> <mvc:default-servlet-handler/> <mvc:annotation-driven/> <context:component-scan base-package="com.wenteryan"></context:component-scan> <bean> <property name="prefix" value="/"></property> <property name="suffix" value=".jsp"></property> <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"></property> </bean> <bean id="multipartResolver" > <property name="defaultEncoding" value="UTF-8"></property> <property name="maxUploadSize" value="10485760000"></property> <property name="maxInMemorySize" value="40960"></property> </bean></beans>
3.编写action
WatermarkAction .action
package com.wenteryan.watermarkspringmvc;import javax.servlet.http.HttpSession;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestMethod;import org.springframework.web.bind.annotation.RequestParam;import org.springframework.web.multipart.commons.CommonsMultipartFile;import org.springframework.web.servlet.ModelAndView;import com.wenteryan.service.MarkService;import com.wenteryan.service.UploadService;@Controllerpublic class WatermarkAction { private MarkService mackService ; private UploadService uploadService ; @RequestMapping(value="/watermark", method=RequestMethod.POST) public ModelAndView watermark( @RequestParam("image")CommonsMultipartFile file, HttpSession session) throws Exception { String uploadPath = "/images" ; String realUploadPath = session.getServletContext().getRealPath(uploadPath) ; String imageUrl = uploadService.uploadImage(file, uploadPath, realUploadPath) ; String logoImageUrl = mackService.watermark(file, uploadPath, realUploadPath) ; ModelAndView ret = new ModelAndView() ; ret.addObject("imageUrl", imageUrl) ; ret.addObject("logoImageUrl", logoImageUrl) ; ret.setViewName("watermark"); return ret ; } @Autowired public void setMackService(MarkService mackService) { this.mackService = mackService; } @Autowired public void setUploadService(UploadService uploadService) { this.uploadService = uploadService; }}4.编写服务类
MarkService .java
package com.wenteryan.service;import java.awt.Color;import java.awt.Font;import java.io.File;import org.springframework.web.multipart.commons.CommonsMultipartFile;public interface MarkService { public static final String MARK_TEXT = "wenteryan" ; public static final String FONT_NAME = "微软雅黑" ; public static final int FONT_SIZE = 120 ; public static final int FONT_STYPE = Font.BOLD ; public static final Color FONT_COLOR = Color.RED ; public static final int X = 10 ; public static final int Y = 10 ; public static float ALPHA = 0.3F ; public String watermark(CommonsMultipartFile file, String uploadPath, String realUploadPath) ; }5.编写接口实现类
UploadService .java
package com.wenteryan.service.impl;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import org.springframework.stereotype.Service;import org.springframework.web.multipart.commons.CommonsMultipartFile;@Servicepublic class UploadService { public String uploadImage(CommonsMultipartFile file, String uploadPath, String realUploadPath) { InputStream is = null ; OutputStream os = null ; try { is = file.getInputStream() ; os = new FileOutputStream(realUploadPath+"/"+file.getOriginalFilename()) ; byte[] buffer = new byte[1024] ; int len = 0 ; while((len=is.read(buffer))>0) { os.write(buffer) ; } } catch(Exception e) { e.printStackTrace() ; } finally { if(is!=null) { try { is.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } if(os!=null) { try { os.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } return uploadPath+"/"+file.getOriginalFilename() ; }}MarkServiceImpl .java
package com.wenteryan.service.impl;import java.awt.AlphaComposite;import java.awt.Font;import java.awt.Graphics2D;import java.awt.Image;import java.awt.image.BufferedImage;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import javax.imageio.ImageIO;import org.springframework.stereotype.Service;import org.springframework.web.multipart.commons.CommonsMultipartFile;import com.sun.image.codec.jpeg.JPEGCodec;import com.sun.image.codec.jpeg.JPEGImageEncoder;import com.wenteryan.service.MarkService;@Servicepublic class MarkServiceImpl implements MarkService { @Override public String watermark(CommonsMultipartFile file, String uploadPath, String realUploadPath) { // TODO Auto-generated method stub String logoFileName = "logo"+file.getOriginalFilename() ; OutputStream os = null ; try { Image image2 = ImageIO.read(file.getInputStream()) ; int width = image2.getWidth(null) ; int height = image2.getHeight(null) ; BufferedImage bufferImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB) ; Graphics2D g = bufferImage.createGraphics() ; g.drawImage(image2, 0, 0, width, height, null) ; g.setFont(new Font(FONT_NAME,FONT_STYPE,FONT_SIZE)); g.setColor(FONT_COLOR) ; int width1 = FONT_SIZE*getTextLength(MARK_TEXT) ; int height1 = FONT_SIZE ; int widthDiff = width-width1 ; int heightDiff = height-height1 ; int x = X ; int y = Y ; if(x>widthDiff) { x = widthDiff ; } if(y>heightDiff) { y=heightDiff ; } g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, ALPHA)); g.drawString(MARK_TEXT, x, y+FONT_SIZE) ; g.dispose() ; os = new FileOutputStream(realUploadPath+"/"+logoFileName) ; JPEGImageEncoder en = JPEGCodec.createJPEGEncoder(os) ; en.encode(bufferImage) ; } catch(Exception e) { e.printStackTrace() ; } finally { if(os!=null) { try { os.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } return uploadPath+"/"+logoFileName; } public int getTextLength(String text) { int length = text.length(); for(int i=0; i<text.length(); i++) { String s = String.valueOf(text.charAt(i)) ; if(s.getBytes().length>1) { length++ ; } } length = length%2==0?length/2:length/2+1 ; return length ; }}6.编写页面
index.jsp
<form action="watermark" method="post" enctype="multipart/form-data"> <h2>请选择上传的图片</h2> <div> <br> <input type="file" name="image" id="image" /> </div> <div> <br> <button type="submit">开始上传</button> </div> </form>
watermark.jsp
<div> <img src="${pageContext.request.contextPath}${imageUrl }"/> <img src="${pageContext.request.contextPath}${logoImageUrl }"/> <a href="${pageContext.request.contextPath }">返回</a> </div>总结
Java有专门Image的处理包，同样应该可以实现水印功能，查了资料小试下来发现java实现水印还是非常方便的，水印可以是图片或者文字，后期会有水印图片水印，以后有需要可以写个代码批量处理自己的图片了。
以上就是本文的全部内容，希望对大家学习java程序设计有所帮助。