本文实例为大家分享了java实现上传图片尺寸修改和质量压缩的具体代码，供大家参考，具体内容如下
package com.zity.frame.util;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;
import net.sourceforge.pinyin4j.PinyinHelper;
import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.*;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.util.Random;
public class CompressPic {
private File file = null; // 文件对象
private String inputDir; // 输入图路径
private String outputDir; // 输出图路径
private String inputFileName; // 输入图文件名
private String outputFileName; // 输出图文件名
private int outputWidth = 300; // 默认输出图片宽
private int outputHeight = 150; // 默认输出图片高
private boolean proportion = true; // 是否等比缩放标记(默认为等比缩放)
public CompressPic() { // 初始化变量
inputDir = "";
outputDir = "";
inputFileName = "";
outputFileName = "";
outputWidth = 300;
outputHeight = 150;
}
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;
}
public long getPicSize(String path) {
file = new File(path);
return file.length();
}
public String compressPic() {
try {
//获得源文件
file = new File(inputDir + inputFileName);
if (!file.exists()) {
return "";
}
// 生成存储路径
File outDir = new File(outputDir);
if(!outDir.exists()){
outDir.mkdirs();
}
Image img = ImageIO.read(file);
// 判断图片格式是否正确
if(img==null){
return "";
}
if (img.getWidth(null) == -1) {
System.out.println(" can't read,retry!" + "<BR>");
return "no";
} else {
int newWidth; int newHeight;
// 判断是否是等比缩放
if (this.proportion == true) {
// 为等比缩放计算输出的图片宽度及高度
int w =img.getWidth(null);
int h = img.getHeight(null);
//如果图片的宽度小于等于250，并且高度小于等于183，图片原样输出
if(w<=300){
outputWidth=w;
}
if(h<=150){
outputHeight=h;
}
double rate1 = ((double) img.getWidth(null)) / (double) outputWidth;
double rate2 = ((double) img.getHeight(null)) / (double) outputHeight;
// 根据缩放比率大的进行缩放控制
// double rate = rate1 > rate2 ? rate1 : rate2;
// 保证宽度为250px
double rate = rate1;
newWidth = (int) (((double) img.getWidth(null)) / rate);
newHeight = (int) (((double) img.getHeight(null)) / rate2);
} else {
newWidth = outputWidth; // 输出的图片宽度
newHeight = outputHeight; // 输出的图片高度
}
//重新设置高宽为图片真实高宽,上面的高宽是其他项目需要300*150的,我没得空删掉
newWidth = getImgWidth(file);
newHeight = getImgHeight(file);
BufferedImage tag = new BufferedImage((int) newWidth, (int) newHeight, BufferedImage.TYPE_INT_RGB);
tag.getGraphics().drawImage(img.getScaledInstance(newWidth, newHeight, Image.SCALE_SMOOTH), 0, 0, null);
FileOutputStream out = new FileOutputStream(outputDir + outputFileName);
// JPEGImageEncoder可适用于其他图片类型的转换
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) {
// 输入图路径
this.inputDir = inputDir;
// 输出图路径
this.outputDir = outputDir;
// 输入图文件名
this.inputFileName = inputFileName;
// 输出图文件名
this.outputFileName = outputFileName;
return compressPic();
}
public String compressPic(String inputDir, String outputDir, String inputFileName, String outputFileName, int width, int height, boolean gp) {
// 输入图路径
this.inputDir = inputDir;
// 输出图路径
this.outputDir = outputDir;
// 输入图文件名
this.inputFileName = inputFileName;
// 输出图文件名
this.outputFileName = outputFileName;
// 设置图片长宽
setWidthAndHeight(width, height);
// 是否是等比缩放 标记
this.proportion = gp;
return compressPic();
}
public String ImageCompression(String downloadUrl,String inputDir,String outDir){
Random rnd = new Random();
String picName = downloadUrl.substring(downloadUrl.lastIndexOf("/")+1);
String extendName ="";
String beforeName= "";
if(picName.contains(".")){
extendName = picName.substring(picName.indexOf("."));
beforeName= picName.substring(0,picName.indexOf("."));
}else{
extendName = picName;
beforeName= picName;
}
//随机数
Integer r = rnd.nextInt(1000);
beforeName = new CompressPic().getPinYinHeadChar(beforeName);
long ts = System.currentTimeMillis();
String outpicName=ts+beforeName+r+".jpg";
outpicName = outpicName.replace("%", "");
if(outpicName.contains("张栋杰总经理会见旭阳集团董事长杨雪岗")){
outpicName="zdjzjlhjxyjtdszyxg.jpg";
}
if(httpDownload(downloadUrl, inputDir, outpicName)){
// 当前时间
// String curTime = new Long(System.currentTimeMillis()).toString();
this.compressPic(inputDir, outDir, outpicName, outpicName, 300, 150, true);
return outpicName;
}else {
return null;
}
}
public static boolean httpDownload(String httpUrl,String saveDir,String saveName){
// 下载网络文件
int bytesum = 0;
int byteread = 0;
URL url = null;
try {
url = new URL(httpUrl);
} catch (MalformedURLException e1) {
e1.printStackTrace();
return false;
}
// 存储目录
File outDir = new File(saveDir);
if(!outDir.exists()){
outDir.mkdirs();
}
try {
URLConnection conn = url.openConnection();
InputStream inStream = conn.getInputStream();
FileOutputStream fs = new FileOutputStream(saveDir+saveName);
byte[] buffer = new byte[1204];
while ((byteread = inStream.read(buffer)) != -1) {
bytesum += byteread;
fs.write(buffer, 0, byteread);
}
fs.close();
inStream.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
return false;
} catch (IOException e) {
e.printStackTrace();
return false;
}
return true;
}
public String getPinYinHeadChar(String str) {
String convert = "";
for (int j = 0; j < str.length(); j++) {
char word = str.charAt(j);
// 提取汉字的首字母
String[] pinyinArray = PinyinHelper.toHanyuPinyinStringArray(word);
if (pinyinArray != null) {
convert += pinyinArray[0].charAt(0);
} else {
convert += word;
}
}
return convert;
}
public static void main(String[] arg) {
CompressPic mypic = new CompressPic();
mypic.compressPic("C:\\Users\\mazhaoxu\\Desktop\\", "C:\\Users\\mazhaoxu\\Desktop\\", "微信图片_20180712182800.png", "2019061818542824511111111111.png");
// if(httpDownload("http://221.195.72.44:8122/NR/rdonlyres/B5071DE7-9652-44AF-9534-0EE0ED2DCA92/15177/resource_651768621.jpg", "D:\\data\\resource_651768621.jpg")){
// int start = (int) System.currentTimeMillis(); // 开始时间
// mypic.compressPic("D:\\data\\", "D:\\data\\", "resource_651768621.jpg", "r1"+start+".jpg", 250, 250, true);
// }
// String s= mypic.getPinYinHeadChar("http://114.251.186.42:81/web-s/images/1447069462915xfydh1_fb_fb521.jpg");
// mypic.ImageCompression("http://114.251.186.42:81/web-s/images/mobile/1447069462915xfydh1_fb_fb521.jpg","d:\\images\\", "d:\\images\\mobile\\");
// mypic.compressPic("d:\\", "d:\\image\\mobile", "144921941137520151204fgw1747.jpg", "144921941137520151204fgw1747.jpg");
// String s = "/image/dslfsjss/image/sisis /image";
// System.out.println(s.replace("/image/", "/mobile/image/"));
}
public static int getImgWidth(File file) {
InputStream is = null;
BufferedImage src = null;
int ret = -1;
try {
is = new FileInputStream(file);
src = javax.imageio.ImageIO.read(is);
ret = src.getWidth(null); // 得到源图宽
is.close();
} catch (Exception e) {
e.printStackTrace();
}
return ret;
}
public static int getImgHeight(File file) {
InputStream is = null;
BufferedImage src = null;
int ret = -1;
try {
is = new FileInputStream(file);
src = javax.imageio.ImageIO.read(is);
ret = src.getHeight(null); // 得到源图高
is.close();
} catch (Exception e) {
e.printStackTrace();
}
return ret;
}
} 这是我用的工具类,其中里面业务会用到pinyin4j的jar包，和图片压缩关系不大，可以去除，我是因为比较着急改完，就没动，如果不想改,需要引入pinyin4j的jar包。
maven:
<!-- https://mvnrepository.com/artifact/com.belerweb/pinyin4j -->
<dependency>
<groupId>com.belerweb</groupId>
<artifactId>pinyin4j</artifactId>
<version>2.5.0</version>
</dependency>可以自行用上面工具类里的main方法进行测试
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持编程网。
