使用Java为图片添加水印

首先新建Web项目，建立完成之后，新建各种文件，新建完成之后项目结构图如下所示:



ImageMarkService.java

package com.watermart;

import java.awt.AlphaComposite;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.OutputStream;

import javax.imageio.ImageIO;

import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;

public class ImageMarkService implements MarkService {

@Override
public String watermark(File image, String imageFileName,
String uploadPath, String realUploadPath) {
/**水印图片相关信息Start**/
String logoFileName = "logo_"+imageFileName;
OutputStream os = null;
/**水印图片相关信息End**/

//Logo的路径
String logoPath=realUploadPath + "/" + LOGO;

try {
//获取传过来的图片的宽和高
Image readImage = ImageIO.read(image);
int width = readImage.getWidth(null);
int height = readImage.getHeight(null);
//1.
BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
//2.
Graphics2D g = bufferedImage.createGraphics();
//3.
g.drawImage(readImage, 0, 0, width, height,null);
//4.
//操作logo文件
File logo = new File(logoPath);
Image logoImage = ImageIO.read(logo);
int logoWidth = logoImage.getWidth(null);
int logoHeight = logoImage.getHeight(null);

int widthDiff = width-logoWidth;
int heightDiff = height-logoHeight;

int x = X;
int y = Y;

if(x>widthDiff){
x = widthDiff;
}
if(y>heightDiff){
y = heightDiff;
}
//透明度
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, ALPHA));
g.drawString(MARK_TEXT, x, y+FONT_SIZE);
g.drawImage(logoImage, x, y, null);
g.dispose();
//5.
os = new FileOutputStream(realUploadPath+"/"+logoFileName);
System.out.println("添加图片水印的文件:"+realUploadPath+"/"+logoFileName);
//6.
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(os);
encoder.encode(bufferedImage);
} catch (Exception e) {
e.printStackTrace();
}finally{
try {
if(os != null){
os.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
return uploadPath+"/"+logoFileName;
}

}

MarkService.java

7fe0

package com.watermart;

import java.awt.Color;
import java.awt.Font;
import java.io.File;

/** * Mark接口 */
public interface MarkService {
/*一些参数的设置*/
public static final String MARK_TEXT = "测试水印文字";//水印文字
public static final String FONT_NAME = "微软雅黑";
public static final int FONT_STYLE = Font.BOLD;
public static final int FONT_SIZE = 120;
public static final Color FONT_COLOR = Color.BLACK;
//文字的位置
public static final int X=10;
public static final int Y=10;
//水印的透明度
public static final float ALPHA=0.3F;
//水印图片的名称
public static final String LOGO="logo.png";

String watermark(File image,String imageFileName,String uploadPath,String realUploadPath);

}

PicInfo.java

package com.watermart;

/** * 图片信息 * * 封装 */
public class PicInfo {

/** * 图片地址URL */
private String imageURL;
/** * 水印图片地址URL */
private String logoImageURL;

public String getImageURL() {
return imageURL;
}
public void setImageURL(String imageURL) {
this.imageURL = imageURL;
}
public String getLogoImageURL() {
return logoImageURL;
}
public void setLogoImageURL(String logoImageURL) {
this.logoImageURL = logoImageURL;
}
}

TextMarkService.java

package com.watermart;

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.OutputStream;

import javax.imageio.ImageIO;

import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;

public class TextMarkService implements MarkService {

@Override
public String watermark(File image, String imageFileName,
String uploadPath, String realUploadPath) {
/**水印图片相关信息Start**/
String logoFileName = "logo_"+imageFileName;
OutputStream os = null;
/**水印图片相关信息End**/

try {
//获取传过来的图片的宽和高
Image readImage = ImageIO.read(image);
int width = readImage.getWidth(null);
int height = readImage.getHeight(null);
//1.
BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
//2.
Graphics2D g = bufferedImage.createGraphics();
//3.
g.drawImage(readImage, 0, 0, width, height,null);
//4.
g.setFont(new Font(FONT_NAME,FONT_STYLE,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;
}
//透明度
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, ALPHA));
g.drawString(MARK_TEXT, x, y+FONT_SIZE);
g.dispose();
//5.
os = new FileOutputStream(realUploadPath+"/"+logoFileName);
System.out.println("添加文字水印的文件:"+realUploadPath+"/"+logoFileName);
//6.
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(os);
encoder.encode(bufferedImage);
} catch (Exception e) {
e.printStackTrace();
}finally{
try {
if(os != null){
os.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
return uploadPath+"/"+logoFileName;
}

/** * 获得文本长度值 * @param text * @return */
public int getTextLength(String text){
int length = text.length();
for (int i = 0; i < length; i++) {
String s=String.valueOf(text.charAt(i));
//判断是中文还是英文 一个中文==2个英文
if(s.getBytes().length>1){
length++;
}
}
length = length%2==0?length/2:length/2+1;
return length;
}
}

UploadService.java

package com.watermart;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

/** * 上传服务类 */
public class UploadService {
/** * 上传图片 * @param image 图片 * @param imageFileName 图片名称 * @param uploadPath 上传路径 * @param realUploadPath 上传的真实路径 存储在磁盘中的文件路径 * @return 文件路径 */
@SuppressWarnings("unused")
public String uploadImage(File image,String imageFileName,String uploadPath,String realUploadPath){
//输入流
InputStream is = null;
//输出流
OutputStream os = null;

try {
//将网页中上传的文件放进内存中，之后可以操作了
is = new FileInputStream(image);
//输出流
os = new FileOutputStream(realUploadPath + "/" + imageFileName);

System.out.println("存储文件的地方:"+realUploadPath + "/" + imageFileName);
byte[] buffer = new byte[1024];
int len = 0;
while((len=is.read(buffer))>0){
//将缓存区中的数据写出去
os.write(buffer);
}
} catch (Exception e) {
e.printStackTrace();
}finally{
if(is!=null){
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}

if(os!=null){
try {
os.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
//返回文件路径
return uploadPath + "/" + imageFileName;
}
}

WaterMarkAction.java

package com.watermart;

import java.io.File;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionSupport;

public class WaterMarkAction extends ActionSupport {
private static final long serialVersionUID = 2925392814200518331L;

private File image; //上传的文件
private String imageFileName; //图片文件名称不能包含中文，否则会上传失败
private String uploadPath; //上传路径

//图片信息
private PicInfo picInfo = new PicInfo();

public PicInfo getPicInfo() {
return picInfo;
}

public void setPicInfo(PicInfo picInfo) {
this.picInfo = picInfo;
}

public String getUploadPath() {
return uploadPath;
}

public void setUploadPath(String uploadPath) {
this.uploadPath = uploadPath;
}

public String watermark() throws Exception{
//获取文件上传的地址
String realUploadPath = ServletActionContext.getServletContext().getRealPath(uploadPath);
//构建服务类
UploadService uploadService = new UploadService();
//写入硬盘后，获取文件存放的位置
String imageURL = uploadService.uploadImage(image, imageFileName, uploadPath, realUploadPath);
//存入文件的地址，用于前台的显示
picInfo.setImageURL(imageURL);

MarkService markService = new ImageMarkService();
picInfo.setLogoImageURL(markService.watermark(image, imageFileName, uploadPath, realUploadPath));
return SUCCESS;
}

public File getImage() {
return image;
}

public void setImage(File image) {
this.image = image;
}

public String getImageFileName() {
return imageFileName;
}

public void setImageFileName(String imageFileName) {
this.imageFileName = imageFileName;
}
}

struts.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN" "http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
<!-- 模式配置 开发模式 -->
<constant name="struts.devMode" value="true" />

<!-- 配置请求后缀 -->
<constant name="struts.action.extension" value="action" />
<!-- 编码配置 -->
<constant name="struts.i18n.encoding" value="UTF-8" />
<!-- 文件上传大小配置 -->
<constant name="struts.multipart.maxSize" value="1073741824" />
<!-- 设置上传文件的临时文件夹 -->
<constant name="struts.multipart.saveDir" value="/tmpUpload" />

<package name="default" namespace="/" extends="struts-default">
<action name="watermark" class="com.watermart.WaterMarkAction" method="watermark">
<!-- 配置参数信息 -->
<param name="uploadPath">/images</param>

<result name="success">watermark.jsp</result>
</action>
</package>

</struts>

index.jsp

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN" "http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
<!-- 模式配置 开发模式 -->
<constant name="struts.devMode" value="true" />

<!-- 配置请求后缀 -->
<constant name="struts.action.extension" value="action" />
<!-- 编码配置 -->
<constant name="struts.i18n.encoding" value="UTF-8" />
<!-- 文件上传大小配置 -->
<constant name="struts.multipart.maxSize" value="1073741824" />
<!-- 设置上传文件的临时文件夹 -->
<constant name="struts.multipart.saveDir" value="/tmpUpload" />

<package name="default" namespace="/" extends="struts-default">
<action name="watermark" class="com.watermart.WaterMarkAction" method="watermark">
<!-- 配置参数信息 -->
<param name="uploadPath">/images</param>

<result name="success">watermark.jsp</result>
</action>
</package>

</struts>

watermark.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@taglib uri="/struts-tags" prefix="s"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>处理结果</title>
</head>
<body>
<table width="100%" align="center" border="1">
<tr>
<td width="50%">
<img src="${pageContext.request.contextPath}<s:property value="picInfo.imageURL" />">
</td>
<td width="50%">
<img src="${pageContext.request.contextPath}<s:property value="picInfo.logoImageURL" />">
</td>
</tr>
</table>
</body>
</html>

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>WaterMaker</display-name>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>

<filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
</web-app>

效果图