圖片格式和大小處理工具類

package com.ytmr;
 
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import javax.imageio.ImageIO;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;

public class IMGUtils {
     private File file = null; // 文件對象 
	 private String inputDir; // 輸入圖路徑
	 private String outputDir; // 輸出圖路徑
	 private String inputFileName; // 輸入圖文件名
	 private String outputFileName; // 輸出圖文件名
	 private int outputWidth = 100; // 默認輸出圖片寬
	 private int outputHeight = 100; // 默認輸出圖片高
	 private boolean proportion = true; // 是否等比縮放標記(默認爲等比縮放)
	 public IMGUtils() { // 初始化變量
		 inputDir = ""; 
		 outputDir = ""; 
		 inputFileName = ""; 
		 outputFileName = ""; 
		 outputWidth = 100; 
		 outputHeight = 100; 
	 } 
	 public void setInputDir(String inputDir) { 
		 this.inputDir = inputDir; 
	 } 
	 public void setOutputDir(String outputDir) { 
		 this.outputDir = outputDir; 
	 } 
	 public void setInputFileName(String inputFileName) { 
		 this.inputFileName = inputFileName;
	 } 
	 public void setOutputFileName(String outputFileName) { 
		 this.outputFileName = outputFileName; 
	 } 
	 public void setOutputWidth(int outputWidth) {
		 this.outputWidth = outputWidth; 
	 } 
	 public void setOutputHeight(int outputHeight) { 
		 this.outputHeight = outputHeight; 
	 } 
	 public void setWidthAndHeight(int width, int height) { 
		 this.outputWidth = width;
		 this.outputHeight = height; 
	 } 

	 /* 
	  * 獲得圖片大小 
	  * 傳入參數 String path ：圖片路徑 
	  */ 
	 public long getPicSize(String path) { 
		 file = new File(path); 
		 return file.length(); 
	 }

	 // 圖片處理 
	 public String compressPic() { 
		 try { 
			 //獲得源文件 
			 file = new File(inputDir + inputFileName); 
			 if (!file.exists()) { 
				 return ""; 
			 } 
			 Image img = ImageIO.read(file); 
			 // 判斷圖片格式是否正確 
			 if (img.getWidth(null) == -1) {
				 System.out.println(" can't read,retry!" + "<BR>"); 
				 return "no"; 
			 } else { 
				 int newWidth; int newHeight; 
				 // 判斷是否是等比縮放 
				 if (this.proportion == true) { 
					 // 爲等比縮放計算輸出的圖片寬度及高度 
					 double rate1 = ((double) img.getWidth(null)) / (double) outputWidth + 0.1; 
					 double rate2 = ((double) img.getHeight(null)) / (double) outputHeight + 0.1; 
					 // 根據縮放比率大的進行縮放控制 
					 double rate = rate1 > rate2 ? rate1 : rate2; 
					 newWidth = (int) (((double) img.getWidth(null)) / rate); 
					 newHeight = (int) (((double) img.getHeight(null)) / rate); 
				 } else { 
					 newWidth = outputWidth; // 輸出的圖片寬度 
	                 newHeight = outputHeight; // 輸出的圖片高度 
				 } 
			 	BufferedImage tag = new BufferedImage((int) newWidth, (int) newHeight, BufferedImage.TYPE_INT_RGB); 

			 	/*
				 * Image.SCALE_SMOOTH 的縮略算法 生成縮略圖片的平滑度的
				 * 優先級比速度高 生成的圖片質量比較好 但速度慢
				 */ 
			 	tag.getGraphics().drawImage(img.getScaledInstance(newWidth, newHeight, Image.SCALE_SMOOTH), 0, 0, null);
			 	FileOutputStream out = new FileOutputStream(outputDir + outputFileName);
			 	// JPEGImageEncoder可適用於其他圖片類型的轉換 
			 	JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out); 
			 	encoder.encode(tag); 
			 	out.close(); 
			 } 
		 } catch (IOException ex) { 
			 ex.printStackTrace(); 
		 } 
		 return "ok"; 
	} 
 	public String compressPic (String inputDir, String outputDir, String inputFileName, String outputFileName) { 
 		// 輸入圖路徑 
 		this.inputDir = inputDir; 
 		// 輸出圖路徑 
 		this.outputDir = outputDir; 
 		// 輸入圖文件名 
 		this.inputFileName = inputFileName; 
 		// 輸出圖文件名
 		this.outputFileName = outputFileName; 
 		return compressPic(); 
 	} 
 	public String compressPic(String inputDir, String outputDir, String inputFileName, String outputFileName, int width, int height, boolean gp) { 
 		// 輸入圖路徑 
 		this.inputDir = inputDir; 
 		// 輸出圖路徑 
 		this.outputDir = outputDir; 
 		// 輸入圖文件名 
 		this.inputFileName = inputFileName; 
 		// 輸出圖文件名 
 		this.outputFileName = outputFileName; 
 		// 設置圖片長寬
 		setWidthAndHeight(width, height); 
 		// 是否是等比縮放 標記 
 		this.proportion = gp; 
 		return compressPic(); 
 	} 

 	// compressPic(大圖片路徑,生成小圖片路徑,大圖片文件名,生成小圖片文名,生成小圖片寬度,生成小圖片高度,是否等比縮放(默認爲true))
 	public static void main(String[] arg) { 
 		IMGUtils mypic = new IMGUtils(); 
 		System.out.println("輸入的圖片大小：" + mypic.getPicSize("e:\\1.jpg")/1024 + "KB"); 
                mypic.compressPic("e:\\", "e:\\test\\", "1.jpg", "r1.jpg", 120, 120, false); 

 	} 
}