我們經(jīng)常會在一些圖片或者圖片上看到某某公司或品牌的水印，那么我們可不可以自己在喜歡的圖片或文件上添加水印呢？答案當(dāng)然是沒問題。
我們先來看看圖片水?。?/p>
----------------------------圖片水印----------------------------
1、添加文字水印
import?java.awt.Color;
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?javax.imageio.ImageIO;
/**
?*?給圖片添加文字水印
?*?
?*?@author?liqiang
?*
?*/
public?class?WaterMarkUtils?{
????/**
?????*?@param?args
?????*/
????public?static?void?main(String[]?args)?{
????????//?原圖位置,?輸出圖片位置,?水印文字顏色,?水印文字
????????new?WaterMarkUtils().mark("C:/Users/liqiang/Desktop/圖片/kdmt.jpg",?"C:/Users/liqiang/Desktop/圖片/kdmt1.jpg",
????????????????Color.red,?"圖片來源:XXX");
????}
????/**
?????*?圖片添加水印
?????*?
?????*?@param?srcImgPath
?????*????????????需要添加水印的圖片的路徑
?????*?@param?outImgPath
?????*????????????添加水印后圖片輸出路徑
?????*?@param?markContentColor
?????*????????????水印文字的顏色
?????*?@param?waterMarkContent
?????*????????????水印的文字
?????*/
????public?void?mark(String?srcImgPath,?String?outImgPath,?Color?markContentColor,?String?waterMarkContent)?{
????????try?{
????????????//?讀取原圖片信息
????????????File?srcImgFile?=?new?File(srcImgPath);
????????????Image?srcImg?=?ImageIO.read(srcImgFile);
????????????int?srcImgWidth?=?srcImg.getWidth(null);
????????????int?srcImgHeight?=?srcImg.getHeight(null);
????????????//?加水印
????????????BufferedImage?bufImg?=?new?BufferedImage(srcImgWidth,?srcImgHeight,?BufferedImage.TYPE_INT_RGB);
????????????Graphics2D?g?=?bufImg.createGraphics();
????????????g.drawImage(srcImg,?0,?0,?srcImgWidth,?srcImgHeight,?null);
????????????//?Font?font?=?new?Font("Courier?New",?Font.PLAIN,?12);
????????????Font?font?=?new?Font("宋體",?Font.PLAIN,?20);
????????????g.setColor(markContentColor);?//?根據(jù)圖片的背景設(shè)置水印顏色
????????????g.setFont(font);
????????????int?x?=?srcImgWidth?-?getWatermarkLength(waterMarkContent,?g)?-?3;
????????????int?y?=?srcImgHeight?-?3;
????????????//?int?x?=?(srcImgWidth?-?getWatermarkLength(watermarkStr,?g))?/?2;
????????????//?int?y?=?srcImgHeight?/?2;
????????????g.drawString(waterMarkContent,?x,?y);
????????????g.dispose();
????????????//?輸出圖片
????????????FileOutputStream?outImgStream?=?new?FileOutputStream(outImgPath);
????????????ImageIO.write(bufImg,?"jpg",?outImgStream);
????????????outImgStream.flush();
????????????outImgStream.close();
????????}?catch?(Exception?e)?{
????????????e.printStackTrace();
????????}
????}
????/**
?????*?獲取水印文字總長度
?????*?
?????*?@param?waterMarkContent
?????*????????????水印的文字
?????*?@param?g
?????*?@return?水印文字總長度
?????*/
????public?int?getWatermarkLength(String?waterMarkContent,?Graphics2D?g)?{
????????return?g.getFontMetrics(g.getFont()).charsWidth(waterMarkContent.toCharArray(),?0,?waterMarkContent.length());
????}
}
結(jié)果：
2、給圖片添加圖片水印
import?java.awt.AlphaComposite;
import?java.awt.Graphics2D;
import?java.awt.Image;
import?java.awt.RenderingHints;
import?java.awt.image.BufferedImage;
import?java.io.File;
import?java.io.FileOutputStream;
import?java.io.OutputStream;
import?javax.imageio.ImageIO;
import?javax.swing.ImageIcon;
/**
?*?給圖片添加圖片
?*?
?*?@author?liqiang
?*
?*/
public?class?WaterMarkUtils?{
????/**
?????*?@param?args
?????*/
????public?static?void?main(String[]?args)?{
????????String?srcImgPath?=?"C:/Users/liqiang/Desktop/圖片/kdmt.jpg";
????????String?iconPath?=?"C:/Users/liqiang/Desktop/圖片/qlq.jpeg";
????????String?targerPath?=?"C:/Users/liqiang/Desktop/圖片/qlq1.jpeg";
????????String?targerPath2?=?"C:/Users/liqiang/Desktop/圖片/qlq2.jpeg";
????????//?給圖片添加水印
????????WaterMarkUtils.markImageByIcon(iconPath,?srcImgPath,?targerPath);
????????//?給圖片添加水印,水印旋轉(zhuǎn)-45
????????WaterMarkUtils.markImageByIcon(iconPath,?srcImgPath,?targerPath2,?-45);
????}
????/**
?????*?給圖片添加水印
?????*?
?????*?@param?iconPath
?????*????????????水印圖片路徑
?????*?@param?srcImgPath
?????*????????????源圖片路徑
?????*?@param?targerPath
?????*????????????目標(biāo)圖片路徑
?????*/
????public?static?void?markImageByIcon(String?iconPath,?String?srcImgPath,?String?targerPath)?{
????????markImageByIcon(iconPath,?srcImgPath,?targerPath,?null);
????}
????/**
?????*?給圖片添加水印、可設(shè)置水印圖片旋轉(zhuǎn)角度
?????*?
?????*?@param?iconPath
?????*????????????水印圖片路徑
?????*?@param?srcImgPath
?????*????????????源圖片路徑
?????*?@param?targerPath
?????*????????????目標(biāo)圖片路徑
?????*?@param?degree
?????*????????????水印圖片旋轉(zhuǎn)角度
?????*/
????public?static?void?markImageByIcon(String?iconPath,?String?srcImgPath,?String?targerPath,?Integer?degree)?{
????????OutputStream?os?=?null;
????????try?{
????????????Image?srcImg?=?ImageIO.read(new?File(srcImgPath));
????????????BufferedImage?buffImg?=?new?BufferedImage(srcImg.getWidth(null),?srcImg.getHeight(null),
????????????????????BufferedImage.TYPE_INT_RGB);
????????????//?得到畫筆對象
????????????//?Graphics?g=?buffImg.getGraphics();
????????????Graphics2D?g?=?buffImg.createGraphics();
????????????//?設(shè)置對線段的鋸齒狀邊緣處理
????????????g.setRenderingHint(RenderingHints.KEY_INTERPOLATION,?RenderingHints.VALUE_INTERPOLATION_BILINEAR);
????????????g.drawImage(srcImg.getScaledInstance(srcImg.getWidth(null),?srcImg.getHeight(null),?Image.SCALE_SMOOTH),?0,
????????????????????0,?null);
????????????if?(null?!=?degree)?{
????????????????//?設(shè)置水印旋轉(zhuǎn)
????????????????g.rotate(Math.toRadians(degree),?(double)?buffImg.getWidth()?/?2,?(double)?buffImg.getHeight()?/?2);
????????????}
????????????//?水印圖象的路徑?水印一般為gif或者png的，這樣可設(shè)置透明度
????????????ImageIcon?imgIcon?=?new?ImageIcon(iconPath);
????????????//?得到Image對象。
????????????Image?img?=?imgIcon.getImage();
????????????float?alpha?=?0.5f;?//?透明度
????????????g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP,?alpha));
????????????//?表示水印圖片的位置
????????????g.drawImage(img,?150,?300,?null);
????????????g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER));
????????????g.dispose();
????????????os?=?new?FileOutputStream(targerPath);
????????????//?生成圖片
????????????ImageIO.write(buffImg,?"JPG",?os);
????????????System.out.println("圖片完成添加Icon印章。。。。。。");
????????}?catch?(Exception?e)?{
????????????e.printStackTrace();
????????}?finally?{
????????????try?{
????????????????if?(null?!=?os)
????????????????????os.close();
????????????}?catch?(Exception?e)?{
????????????????e.printStackTrace();
????????????}
????????}
????}
}
效果展示：
（免費(fèi)視頻教程：java視頻教程）
------------------------------PDF水印(itext添加水印)----------------------------
在這里就同時(shí)給PDF添加文字水印和圖片水印(每一頁都添加一個(gè)文字水印和圖片水印)
依賴的包：
<dependencies> ????????<dependency> ????????????<groupId>com.lowagie</groupId> ????????????<artifactId>itextasian</artifactId> ????????????<version>1.0</version> ????????</dependency> ????????<dependency> ????????????<groupId>com.lowagie</groupId> ????????????<artifactId>itext</artifactId> ????????????<version>2.1.7</version> ????????</dependency> ????</dependencies>
具體代碼：
import?java.awt.Color;
import?java.io.BufferedOutputStream;
import?java.io.File;
import?java.io.FileOutputStream;
import?java.io.IOException;
import?java.text.SimpleDateFormat;
import?java.util.Calendar;
import?com.lowagie.text.DocumentException;
import?com.lowagie.text.Element;
import?com.lowagie.text.Image;
import?com.lowagie.text.pdf.BaseFont;
import?com.lowagie.text.pdf.PdfContentByte;
import?com.lowagie.text.pdf.PdfGState;
import?com.lowagie.text.pdf.PdfReader;
import?com.lowagie.text.pdf.PdfStamper;
public?class?TestWaterPrint?{
????public?static?void?main(String[]?args)?throws?DocumentException,?IOException?{
????????//?要輸出的pdf文件
????????BufferedOutputStream?bos?=?new?BufferedOutputStream(new?FileOutputStream(new?File("E:/abc.pdf")));
????????Calendar?cal?=?Calendar.getInstance();
????????SimpleDateFormat?format?=?new?SimpleDateFormat("yyyy-MM-dd?hh:mm:ss");
????????//?將pdf文件先加水印然后輸出
????????setWatermark(bos,?"G:/1.pdf",?format.format(cal.getTime())?+?"??下載使用人："?+?"測試user",?16);
????}
????/**
?????*?
?????*?@param?bos輸出文件的位置
?????*?@param?input
?????*????????????原PDF位置
?????*?@param?waterMarkName
?????*????????????頁腳添加水印
?????*?@param?permission
?????*????????????權(quán)限碼
?????*?@throws?DocumentException
?????*?@throws?IOException
?????*/
????public?static?void?setWatermark(BufferedOutputStream?bos,?String?input,?String?waterMarkName,?int?permission)
????????????throws?DocumentException,?IOException?{
????????PdfReader?reader?=?new?PdfReader(input);
????????PdfStamper?stamper?=?new?PdfStamper(reader,?bos);
????????int?total?=?reader.getNumberOfPages()?+?1;
????????PdfContentByte?content;
????????BaseFont?base?=?BaseFont.createFont("STSong-Light",?"UniGB-UCS2-H",?BaseFont.EMBEDDED);
????????PdfGState?gs?=?new?PdfGState();
????????for?(int?i?=?1;?i?<?total;?i++)?{
????????????content?=?stamper.getOverContent(i);//?在內(nèi)容上方加水印
????????????//?content?=?stamper.getUnderContent(i);//在內(nèi)容下方加水印
????????????gs.setFillOpacity(0.2f);
????????????//?content.setGState(gs);
????????????content.beginText();
????????????content.setColorFill(Color.LIGHT_GRAY);
????????????content.setFontAndSize(base,?50);
????????????content.setTextMatrix(70,?200);
????????????content.showTextAligned(Element.ALIGN_CENTER,?"公司內(nèi)部文件，請注意保密！",?300,?350,?55);
????????????Image?image?=?Image.getInstance("G:/2.jpeg");
????????????/*
??????????????img.setAlignment(Image.LEFT?|?Image.TEXTWRAP);
??????????????img.setBorder(Image.BOX);?img.setBorderWidth(10);
??????????????img.setBorderColor(BaseColor.WHITE);?img.scaleToFit(100072);//大小
??????????????img.setRotationDegrees(-30);//旋轉(zhuǎn)
?????????????*/
????????????image.setAbsolutePosition(200,?206);?//?set?the?first?background
????????????????????????????????????????????????????//?image?of?the?absolute
????????????image.scaleToFit(200,?200);
????????????content.addImage(image);
????????????content.setColorFill(Color.BLACK);
????????????content.setFontAndSize(base,?8);
????????????content.showTextAligned(Element.ALIGN_CENTER,?"下載時(shí)間："?+?waterMarkName?+?"",?300,?10,?0);
????????????content.endText();
????????}
????????stamper.close();
????}
}
效果展示：
補(bǔ)充：關(guān)于字體的用法
1、使用iTextAsian.jar中的字體?
BaseFont.createFont("STSong-Light",?"UniGB-UCS2-H",BaseFont.NOT_EMBEDDED);
2、使用Windows系統(tǒng)字體
BaseFont.createFont("C:/WINDOWS/Fonts/SIMYOU.TTF",?BaseFont.IDENTITY_H,BaseFont.NOT_EMBEDDED);
3、使用資源字體(ClassPath) ，也就是將ttf字體拷貝到src目錄
BaseFont.createFont("/SIMYOU.TTF",?BaseFont.IDENTITY_H,BaseFont.NOT_EMBEDDED);
三種方法親測有效，而且使用itext自帶的字體就夠用了，可以正確的處理中文。
補(bǔ)充：關(guān)于獲取PDF頁面高度、寬度然后進(jìn)行動(dòng)態(tài)定位，比如說根據(jù)頁面寬度實(shí)現(xiàn)平鋪水?。?/p>
package?cn.xm.exam.test;
import?java.awt.FontMetrics;
import?java.io.BufferedOutputStream;
import?java.io.File;
import?java.io.FileOutputStream;
import?java.io.IOException;
import?javax.swing.JLabel;
import?com.itextpdf.text.DocumentException;
import?com.itextpdf.text.Element;
import?com.itextpdf.text.Rectangle;
import?com.itextpdf.text.pdf.BaseFont;
import?com.itextpdf.text.pdf.PdfContentByte;
import?com.itextpdf.text.pdf.PdfGState;
import?com.itextpdf.text.pdf.PdfReader;
import?com.itextpdf.text.pdf.PdfStamper;
public?class?TestWaterPrint?{
????public?static?void?main(String[]?args)?throws?DocumentException,?IOException?{
????????//?要輸出的pdf文件
????????BufferedOutputStream?bos?=?new?BufferedOutputStream(new?FileOutputStream(new?File("F:/test1.pdf")));
????????//?將pdf文件先加水印然后輸出
????????setWatermark(bos,?"F:/test.pdf",?"測試user");
????}
????/**
?????*?
?????*?@param?bos輸出文件的位置
?????*?@param?input
?????*????????????原PDF位置
?????*?@param?waterMarkName
?????*????????????頁腳添加水印
?????*?@throws?DocumentException
?????*?@throws?IOException
?????*/
????public?static?void?setWatermark(BufferedOutputStream?bos,?String?input,?String?waterMarkName)
????????????throws?DocumentException,?IOException?{
????????PdfReader?reader?=?new?PdfReader(input);
????????PdfStamper?stamper?=?new?PdfStamper(reader,?bos);
????????//?獲取總頁數(shù)?+1,?下面從1開始遍歷
????????int?total?=?reader.getNumberOfPages()?+?1;
????????//?使用classpath下面的字體庫
????????BaseFont?base?=?null;
????????try?{
????????????base?=?BaseFont.createFont("/calibri.ttf",?BaseFont.IDENTITY_H,?BaseFont.NOT_EMBEDDED);
????????}?catch?(Exception?e)?{
????????????//?日志處理
????????????e.printStackTrace();
????????}
????????//?間隔
????????int?interval?=?-5;
????????//?獲取水印文字的高度和寬度
????????int?textH?=?0,?textW?=?0;
????????JLabel?label?=?new?JLabel();
????????label.setText(waterMarkName);
????????FontMetrics?metrics?=?label.getFontMetrics(label.getFont());
????????textH?=?metrics.getHeight();
????????textW?=?metrics.stringWidth(label.getText());
????????System.out.println("textH:?"?+?textH);
????????System.out.println("textW:?"?+?textW);
????????//?設(shè)置水印透明度
????????PdfGState?gs?=?new?PdfGState();
????????gs.setFillOpacity(0.4f);
????????gs.setStrokeOpacity(0.4f);
????????Rectangle?pageSizeWithRotation?=?null;
????????PdfContentByte?content?=?null;
????????for?(int?i?=?1;?i?<?total;?i++)?{
????????????//?在內(nèi)容上方加水印
????????????content?=?stamper.getOverContent(i);
????????????//?在內(nèi)容下方加水印
????????????//?content?=?stamper.getUnderContent(i);
????????????content.saveState();
????????????content.setGState(gs);
????????????//?設(shè)置字體和字體大小
????????????content.beginText();
????????????content.setFontAndSize(base,?20);
????????????//?獲取每一頁的高度、寬度
????????????pageSizeWithRotation?=?reader.getPageSizeWithRotation(i);
????????????float?pageHeight?=?pageSizeWithRotation.getHeight();
????????????float?pageWidth?=?pageSizeWithRotation.getWidth();
????????????//?根據(jù)紙張大小多次添加，?水印文字成30度角傾斜
????????????for?(int?height?=?interval?+?textH;?height?<?pageHeight;?height?=?height?+?textH?*?3)?{
????????????????for?(int?width?=?interval?+?textW;?width?<?pageWidth?+?textW;?width?=?width?+?textW?*?2)?{
????????????????????content.showTextAligned(Element.ALIGN_LEFT,?waterMarkName,?width?-?textW,?height?-?textH,?30);
????????????????}
????????????}
????????????content.endText();
????????}
????????//?關(guān)流
????????stamper.close();
????????reader.close();
????}
}
結(jié)果展示：
補(bǔ)充：關(guān)于itext添加傾斜字體的水印
上面使用的是BaseFont，無法添加樣式，F(xiàn)ont可以添加樣式，但是setFontAndSize方法不接受Font參數(shù)。所以只能變通實(shí)現(xiàn)：
例如：在每頁右下角生成傾斜水印
package?cn.xm.exam.test;
import?java.io.BufferedOutputStream;
import?java.io.File;
import?java.io.FileOutputStream;
import?java.io.IOException;
import?com.itextpdf.text.DocumentException;
import?com.itextpdf.text.Rectangle;
import?com.itextpdf.text.pdf.BaseFont;
import?com.itextpdf.text.pdf.PdfContentByte;
import?com.itextpdf.text.pdf.PdfGState;
import?com.itextpdf.text.pdf.PdfReader;
import?com.itextpdf.text.pdf.PdfStamper;
public?class?TestWaterPrint?{
????public?static?void?main(String[]?args)?throws?DocumentException,?IOException?{
????????//?要輸出的pdf文件
????????BufferedOutputStream?bos?=?new?BufferedOutputStream(new?FileOutputStream(new?File("F:/test2.pdf")));
????????//?將pdf文件先加水印然后輸出
????????setWatermark(bos,?"F:/test.pdf",?"測試user123456789");
????}
????/**
?????*?
?????*?@param?bos輸出文件的位置
?????*?@param?input
?????*????????????原PDF位置
?????*?@param?waterMarkName
?????*????????????頁腳添加水印
?????*?@throws?DocumentException
?????*?@throws?IOException
?????*/
????public?static?void?setWatermark(BufferedOutputStream?bos,?String?input,?String?waterMarkName)
????????????throws?DocumentException,?IOException?{
????????PdfReader?reader?=?new?PdfReader(input);
????????PdfStamper?stamper?=?new?PdfStamper(reader,?bos);
????????//?獲取總頁數(shù)?+1,?下面從1開始遍歷
????????int?total?=?reader.getNumberOfPages()?+?1;
????????//?使用classpath下面的字體庫
????????BaseFont?base?=?null;
????????try?{
????????????base?=?BaseFont.createFont("/calibri.ttf",?BaseFont.IDENTITY_H,?BaseFont.NOT_EMBEDDED);
????????}?catch?(Exception?e)?{
????????????//?日志處理
????????????e.printStackTrace();
????????}
????????//?設(shè)置水印透明度
????????PdfGState?gs?=?new?PdfGState();
????????gs.setFillOpacity(0.4f);
????????gs.setStrokeOpacity(0.4f);
????????PdfContentByte?content?=?null;
????????for?(int?i?=?1;?i?<?total;?i++)?{
????????????//?在內(nèi)容上方加水印
????????????content?=?stamper.getOverContent(i);
????????????//?在內(nèi)容下方加水印
????????????//?content?=?stamper.getUnderContent(i);
????????????content.saveState();
????????????content.setGState(gs);
????????????//?設(shè)置字體和字體大小
????????????content.beginText();
????????????content.setFontAndSize(base,?10);
????????????//?設(shè)置字體樣式
????????????float?ta?=?1F,?tb?=?0F,?tc?=?0F,?td?=?1F,?tx?=?0F,?ty?=?0F;
????????????//?設(shè)置加粗(加粗)
????????????ta?+=?0.25F;
????????????td?+=?0.05F;
????????????ty?-=?0.2F;
????????????//?設(shè)置傾斜(傾斜程序自己改)
????????????tc?+=?0.8F;
????????????content.setTextMatrix(ta,?tb,?tc,?td,?tx,?ty);
????????????//?設(shè)置相對于左下角位置(向右為x，向上為y)
????????????content.moveText(300F,?5F);
????????????//?顯示text
????????????content.showText(waterMarkName);
????????????content.endText();
????????????content.stroke();
????????????content.restoreState();
????????}
????????//?關(guān)流
????????stamper.close();
????????reader.close();
????}
}
結(jié)果展示：
相關(guān)推薦：java入門教程
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