先看效果:
水印可以是圖片,也可以像我這樣是自定義的文字
需要的庫:
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>simpleimage</artifactId>
<version>1.2.3</version>
</dependency>
<dependency>
<groupId>javax.media.jai</groupId>
<artifactId>com.springsource.javax.media.jai.core</artifactId>
<version>1.1.3</version>
</dependency>
<dependency>
<groupId>javax.media.jai</groupId>
<artifactId>com.springsource.javax.media.jai.codec</artifactId>
<version>1.1.3</version>
</dependency>
代碼:
public static void main(String[] args) {
String url = "http://s.cn.bing.net/th?id=OHR.MetamorphicRocks_ZH-CN9753251368_1920x1080.jpg&rf=LaDigue_1920x1080.jpg";
File file = new File("C:\\Users\\Wu\\Desktop\\1.jpg");
String note = "這是測試水印這是測試水印這是測試水印這是測試水印";
save(url, file, note);
}
// 保存圖片
private static void save(String srcUrl, File saveFile, String note) {
InputStream inputStream = null;
OutputStream outputStream = null;
try {
//獲取輸入流
URL url = new URL(srcUrl);
HttpURLConnection httpUrl = (HttpURLConnection) url.openConnection();
httpUrl.connect();
inputStream = httpUrl.getInputStream();
// 加上水印
BufferedImage bufferedImage = addWaterMark(httpUrl.getInputStream(), note);
// 輸出
// 獲取文件輸出流
outputStream = new FileOutputStream(saveFile);
// 獲取圖片格式
String prefix = saveFile.getName().substring(saveFile.getName().lastIndexOf(".") + 1);
// 輸出圖片
ImageWriteHelper.write(new ImageWrapper(bufferedImage), outputStream, ImageFormat.getImageFormat(prefix), new WriteParameter());
} catch (Exception e) {
e.printStackTrace();
} finally {
IOUtils.closeQuietly(inputStream); // 圖片文件輸入輸出流必須記得關閉
IOUtils.closeQuietly(outputStream);
}
}
// 添加水印 第二個參數爲水印的內容,爲字符串
public static BufferedImage addWaterMark(InputStream in, String note) throws SimpleImageException {
// 獲取照片類
ImageWrapper imageWrapper = ImageReadHelper.read(in);
// 獲取水印照片包裝類
ImageWrapper waterWrapper = new ImageWrapper(getWaterMask(note));
// 計算水印放在哪個位置
Point p = calculate(imageWrapper.getWidth(), imageWrapper.getHeight(), waterWrapper.getWidth(), waterWrapper.getHeight());
// 水印屬性類
WatermarkParameter param = new WatermarkParameter(waterWrapper, 1f, (int) p.getX(), (int) p.getY());
// // 將水印寫到圖片上並返回圖片Buff
return ImageDrawHelper.drawWatermark(imageWrapper.getAsBufferedImage(), param);
}
// 將文字生成爲圖片
private static BufferedImage getWaterMask(String text) {
Color fontColor = new Color(203, 203, 203);
Color bgColor = new Color(0, 0, 0, 178);
Font font = new Font("楷體", Font.PLAIN, 20);
int[] num = getStringWidthAndHeight(text, font);
int width = num[1]; //字符串寬度
int height = num[0]; //字符串高度
float alpha = 0.2f;
BufferedImage buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
//得到畫筆對象
Graphics2D g2d = buffImg.createGraphics();
// 添加背景色
// g2d.setColor(bgColor);
g2d.setColor(bgColor);
g2d.fillRoundRect(0, 0, width, height, 7,7);
// ---------- 增加下面的代碼使得背景透明 -----------------
g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, alpha));
g2d.dispose();
// ---------- 背景透明代碼結束 -----------------
// 添加文字
g2d = buffImg.createGraphics();
// 設置對線段的鋸齒狀邊緣處理
g2d.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
// 設置顏色
g2d.setColor(fontColor);
// 設置 Font
g2d.setFont(font);
//設置透明度:1.0f爲透明度 ,值從0-1.0,依次變得不透明
// g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, alpha));
g2d.drawString(text, 0, height - 5);//居中顯示
//釋放資源
g2d.dispose();
// System.out.println("添加水印文字完成!");
return buffImg;
}
// 獲取文字的高和寬
private static int[] getStringWidthAndHeight(String str, Font font) {
JLabel label = new JLabel();
label.setFont(font);
FontMetrics metrics;
int textH;
int textW;
label.setText(str);
metrics = label.getFontMetrics(font);
textH = metrics.getHeight();//字符串的高, 只和字體有關
textW = metrics.stringWidth(label.getText());//字符串的寬
int[] num = new int[2];
num[0] = textH;
num[1] = textW;
return num;
}
// 計算水印放的位置
private static Point calculate(int parentWidth, int parentHeight, int width, int height) {
int x = (parentWidth - (int)(parentWidth * 0.05)) - width ;
int y = (parentHeight - (int)(parentHeight * 0.1));
return new Point(x, y);
}