base64encoderjava

『壹』 java怎麼在控制台輸出一張jpg的圖片

輸出圖片的base64編碼

//imgFile是圖片的路徑
publicstaticvoidgetImageStr(StringimgFile){
InputStreaminputStream=null;
byte[]data=null;
try{
inputStream=newFileInputStream(imgFile);
data=newbyte[inputStream.available()];
inputStream.read(data);
inputStream.close();
}catch(IOExceptione){
e.printStackTrace();
}//加密
BASE64Encoderencoder=newBASE64Encoder();
System.out.println(encoder.encode(data));
}

『貳』 java base64解碼 怎麼是亂碼呢

會亂碼的原因是你的編碼不一致導致的
php中的urlencode的編碼是和系統編碼一致的(比如windows默認gb2312,ubuntu默認utf-8)
所以首先需要確定你的系統編碼,之後根據得到的系統編碼在調用java的decode方法的時候,將這個編碼傳入(考慮到你的例子中有繁體字,所以,建議你使用utf-8編碼),以下是我使用utf-8編碼的例子(php環境是ubuntun下)

『叄』 JAVA怎麼將pdf的base64轉換成jpg的base64

package com.aiait.base.util;

import org.apache.pdfbox.pdmodel.PDDocument;

import org.apache.pdfbox.rendering.ImageType;

import org.apache.pdfbox.rendering.PDFRenderer;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import com.aiait.base.service.impl.base.SearchServiceImpl;

import org.apache.pdfbox.*;

import java.awt.image.BufferedImage;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.IOException;

import java.io.InputStream;

import java.net.URL;

import java.text.DecimalFormat;

import java.util.Date;

import javax.imageio.ImageIO;

import org.apache.commons.lang3.StringUtils;

import sun.misc.BASE64Decoder;

import sun.misc.BASE64Encoder;

public class PDFUtil {

// logger

private static final Logger lOGGER = LoggerFactory.getLogger(PDFUtil.class);

public static void main(String[] args) {

// pdfTojpg("C://Test//eClaimPDF//1//Others.pdf","C://Test//eClaimPDF//WrittenConfirmation.jpg");

Date timeDiffE = null;

Date timeDiffL = null;

timeDiffE = new Date();

base64PdfToJpg(pdfBase64);

timeDiffL = new Date();

lOGGER.info("base64PdfToJpg use time: " + getDiffTime(timeDiffL, timeDiffE) + "s");

}

private static String base64PdfToJpg(String base64Pdf) {

String jpg_base64 = null;

int pdfdpi = 400;

BASE64Decoder decoder = new BASE64Decoder();

byte[] pdf_bytes = null;

try {

pdf_bytes = decoder.decodeBuffer(base64Pdf);

} catch (IOException e1) {

e1.printStackTrace();

}

try (final PDDocument document = PDDocument.load(pdf_bytes)) {

int size = document.getNumberOfPages();

/*圖像合並使用參數*/

// 定義寬度

int width = 0;

// 保存一張圖片中的RGB數據

int[] singleImgRGB;

// 定義高度，後面用於疊加

int shiftHeight = 0;

//保存每張圖片的像素值

BufferedImage imageResult = null;

// 利用PdfBox生成圖像

PDDocument pdDocument = document;

PDFRenderer renderer = new PDFRenderer(pdDocument);

/*根據總頁數, 按照50頁生成一張長圖片的邏輯, 進行拆分*/

// 每50頁轉成1張圖片

int pageLength = size; //有多少轉多少

// 總計循環的次數

int totalCount = pdDocument.getNumberOfPages() / pageLength + 1;

for (int m = 0; m < totalCount; m++) {

for (int i = 0; i < pageLength; i++) {

int pageIndex = i + (m * pageLength);

if (pageIndex == pdDocument.getNumberOfPages()) {

System.out.println("m = " + m);

break;

}

// 96為圖片的dpi，dpi越大，則圖片越清晰，圖片越大，轉換耗費的時間也越多

BufferedImage image = renderer.renderImageWithDPI(pageIndex, 106, ImageType.RGB);

int imageHeight = image.getHeight();

int imageWidth = image.getWidth();

if (i == 0) {

//計算高度和偏移量

//使用第一張圖片寬度;

width = imageWidth;

// 保存每頁圖片的像素值

// 加個判斷：如果m次循環後所剩的圖片總數小於pageLength，則圖片高度按剩餘的張數繪制，否則會出現長圖片下面全是黑色的情況

if ((pdDocument.getNumberOfPages() - m * pageLength) < pageLength) {

imageResult = new BufferedImage(width, imageHeight * (pdDocument.getNumberOfPages() - m * pageLength), BufferedImage.TYPE_INT_RGB);

} else {

imageResult = new BufferedImage(width, imageHeight * pageLength, BufferedImage.TYPE_INT_RGB);

}

} else {

// 將高度不斷累加

shiftHeight += imageHeight;

}

singleImgRGB = image.getRGB(0, 0, width, imageHeight, null, 0, width);

imageResult.setRGB(0, shiftHeight, width, imageHeight, singleImgRGB, 0, width);

}

// System.out.println("m = " + m);

File outFile = new File("C://Test//eClaimPDF//WrittenConfirmation.png");

System.out.println(outFile.getName());

// 寫圖片

ImageIO.write(imageResult, "png", outFile);

// 這個很重要，下面會有說明

shiftHeight = 0;

}

pdDocument.close();

ByteArrayOutputStream baos = new ByteArrayOutputStream();//io流

ImageIO.write(imageResult, "png", baos);//寫入流中

byte[] jpg_Bytes = baos.toByteArray();//轉換成位元組

BASE64Encoder encoder = new BASE64Encoder();

jpg_base64 = encoder.encodeBuffer(jpg_Bytes).trim();//轉換成base64串

jpg_base64 = jpg_base64.replaceAll(" ", "").replaceAll(" ", "");//刪除

// System.out.println("值為："+"data:image/jpg;base64,"+jpg_base64);

} catch (Exception e) {

e.printStackTrace();

}

return "data:image/jpg;base64,"+jpg_base64;

}

// private static String base64PdfToJpg(String base64Pdf) {

// String jpg_base64 = null;

// int pdfdpi = 400;

//

// BASE64Decoder decoder = new BASE64Decoder();

// byte[] pdf_bytes = null;

// try {

// pdf_bytes = decoder.decodeBuffer(base64Pdf);

// } catch (IOException e1) {

// e1.printStackTrace();

// }

//

// try (final PDDocument document = PDDocument.load(pdf_bytes)) {

// int size = document.getNumberOfPages();

// for (int i = 0; i < size; i++) {

// BufferedImage image = new PDFRenderer(document).renderImageWithDPI(i, pdfdpi, ImageType.RGB);

// BufferedImage image = new PDFRenderer(document).

//

// ByteArrayOutputStream baos = new ByteArrayOutputStream();//io流

// ImageIO.write(image, "jpg", baos);//寫入流中

// byte[] jpg_Bytes = baos.toByteArray();//轉換成位元組

// BASE64Encoder encoder = new BASE64Encoder();

// jpg_base64 = encoder.encodeBuffer(jpg_Bytes).trim();//轉換成base64串

// jpg_base64 = jpg_base64.replaceAll(" ", "").replaceAll(" ", "");//刪除

//

// System.out.println("值為："+"data:image/jpg;base64,"+jpg_base64);

//

// }

// } catch (Exception e) {

// e.printStackTrace();

// }

// return "data:image/jpg;base64,"+jpg_base64;

// }

private static void pdfTojpg(String pdfFilePath, String jpgFilePath) {

File pdfFile = new File(pdfFilePath);

int idx = jpgFilePath.lastIndexOf('.');

String jpgprefix = StringUtils.substring(jpgFilePath, 0, idx);

int pdfdpi = 400;

BASE64Decoder decoder = new BASE64Decoder();

byte[] bytes = null;

try {

bytes = decoder.decodeBuffer(pdfBase64);

} catch (IOException e1) {

e1.printStackTrace();

}

// try (final PDDocument document = PDDocument.load(pdfFile, "")) {

try (final PDDocument document = PDDocument.load(bytes)) {

int size = document.getNumberOfPages();

for (int i = 0; i < size; i++) {

BufferedImage image = new PDFRenderer(document).renderImageWithDPI(i, pdfdpi, ImageType.RGB);

/*

* ByteArrayOutputStream baos = new ByteArrayOutputStream();//io流

* ImageIO.write(image, "jpg", baos);//寫入流中 byte[] imgBytes =

* baos.toByteArray();//轉換成位元組 BASE64Encoder encoder = new BASE64Encoder();

* String png_base64 = encoder.encodeBuffer(imgBytes).trim();//轉換成base64串

* png_base64 = png_base64.replaceAll(" ", "").replaceAll(" ", "");//刪除

*

* System.out.println("值為："+"data:image/jpg;base64,"+png_base64);

*/

File jpgFile = new File(jpgprefix + "_" + i + ".jpg");

ImageIO.write(image, "jpg", jpgFile);

}

} catch (Exception e) {

e.printStackTrace();

}

}

private static Double getDiffTime(Date lateTime, Date earlyTime) {

DecimalFormat df=new DecimalFormat("0.00");//設置保留位數

return Double.valueOf(df.format((double)(lateTime.getTime() - earlyTime.getTime()) / 1000));

}

public static String pdfBase64 = "***" //from web網頁鏈接, upload a PDF to get the base64 string (Base64 - Online Base64 decoder and encoder)

}

『肆』 在Java中如何進行BASE64編碼和解碼

importsun.misc.BASE64Encoder;
importsun.misc.BASE64Decoder;

//將s進行BASE64編碼
publicstaticStringgetBASE64(Strings){
if(s==null)returnnull;
return(newsun.misc.BASE64Encoder()).encode(s.getBytes());
}

//將BASE64編碼的字元串s進行解碼
(Strings){
if(s==null)returnnull;
BASE64Decoderdecoder=newBASE64Decoder();
try{
byte[]b=decoder.decodeBuffer(s);
returnnewString(b);
}catch(Exceptione){
returnnull;
}
}