jSsignature 数字签名，保存图片-优快云博客

这篇博客介绍了如何使用Java进行SVG到PNG的转换，并详细讲解了在JavaScript中实现数字签名的过程，同时提供了相关的jsp页面示例代码。

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获取页面传递字符


String data = req.getParameter("data");
String imageData=data.substring(data.indexOf(",")+2, data.length()-2);
			//System.out.println(imageData.indexOf("\\"));
			//String  s="\\";
			//imageData=imageData.replaceAll(s, " ");
			imageData=imageData.replace('\\', ' ');
			imageData=imageData.replaceAll(" \"", "\"");
			//保存特定的目录下面  读取配置文件的路径
			StringBuffer realPathDir = new StringBuffer();
			realPathDir.append(PropertiesUtil.getProperty("SaveFilePath")+Constant.PACT.CAND_SIGNATURE);
			String path = realPathDir.toString();
			String filename=fix+candId+".png";
			String imgPath = SvgPngConverter.convertToPng(imageData,path,path+"/"+filename);

SvgPngConverter.java


package com.qk365.util;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;

import org.apache.batik.transcoder.TranscoderException;
import org.apache.batik.transcoder.TranscoderInput;
import org.apache.batik.transcoder.TranscoderOutput;
import org.apache.batik.transcoder.image.PNGTranscoder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.qk365.join.comp.action.CanditorMobileController;

/**
 * 将svg转换为png格式的图片
 * 
 * 
 */
public abstract class SvgPngConverter {
	private static Logger logger = LoggerFactory.getLogger(SvgPngConverter.class);
    /**
     * 将svg字符串转换为png
     * 
     * @param svgCode svg代码
     * @param pngFilePath 保存的路径
     * @throws TranscoderException svg代码异常
     * @throws IOException io错误
     */
    public static String convertToPng(String svgCode, String filePah,String pngFilePath) throws IOException,
            TranscoderException {

    	File fileFloder = new File(filePah);
    	if(!fileFloder.exists()){
    		fileFloder.mkdir();
    	}

        //File file = new File(pngFilePath);
        FileOutputStream outputStream = null;
        try {
//            file.createNewFile();
            outputStream = new FileOutputStream(pngFilePath);
            convertToPng(svgCode, outputStream);
            return pngFilePath;
        } finally {
            if (outputStream != null) {
                try {
                    outputStream.close();
                } catch (IOException e) {
                  logger.error("outputStream.close e:",e);
                    return null;
                }
            }
        }
    }

    /**
     * 将svgCode转换成png文件，直接输出到流中
     * 
     * @param svgCode svg代码
     * @param outputStream 输出流
     * @throws TranscoderException 异常
     * @throws IOException io异常
     */
    public static void convertToPng(String svgCode, OutputStream outputStream)
            throws TranscoderException, IOException {
        try {
            byte[] bytes = svgCode.getBytes("utf-8");
            PNGTranscoder t = new PNGTranscoder();
            TranscoderInput input = new TranscoderInput(new ByteArrayInputStream(bytes));
            TranscoderOutput output = new TranscoderOutput(outputStream);
            t.transcode(input, output);
            outputStream.flush();
        } finally {
            if (outputStream != null) {
                try {
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    public static void main(String[] args) {
    	StringBuffer sb=new StringBuffer();
//    	sb.append("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?><!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\" \"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\"><svg xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\" width=\"401\" height=\"36\"><path fill=\"none\" stroke=\"#000000\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" d=\"M 1 1 c 2.12 0 80.27 -1.58 121 0 c 20 0.78 38.73 3.98 59 7 c 37.69 5.61 71.69 12.77 109 18 c 16.27 2.28 31.51 2.25 48 4 c 12.78 1.35 24.53 3.99 37 5 c 8.35 0.67 25 0 25 0\"/></svg>");
    	sb.append("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?><!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\" \"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\"><svg xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\" width=\"456\" height=\"132\"><path fill=\"none\" stroke=\"#000000\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" d=\"M 2 44 c -0.02 0.19 -1.72 7.99 -1 11 c 0.76 3.17 3.72 7.15 6 10 c 1.53 1.91 3.86 3.53 6 5 c 3.2 2.2 6.51 4.45 10 6 c 5.4 2.4 11.31 3.69 17 6 c 6.92 2.81 13.08 6.44 20 9 c 8.58 3.17 17.02 5.98 26 8 c 27.27 6.12 53.42 11.36 81 16 c 10.73 1.8 21.12 1.57 32 3 c 9.96 1.31 18.94 3.55 29 5 c 21.04 3.04 40.39 7 61 8 c 34.85 1.69 69.52 0.59 104 0 c 4.03 -0.07 7.97 -1.12 12 -2 c 3.77 -0.82 7.42 -1.75 11 -3 c 3.1 -1.08 6.13 -2.39 9 -4 c 5.5 -3.08 11.74 -6.06 16 -10 c 4.2 -3.89 7.74 -9.98 11 -15 c 0.94 -1.45 1.43 -3.29 2 -5 c 0.44 -1.31 1 -2.75 1 -4 c 0 -1.85 -0.12 -4.39 -1 -6 c -2.8 -5.14 -6.49 -11.97 -11 -16 c -10.32 -9.23 -23.9 -16.86 -36 -26 c -4.64 -3.5 -8.36 -7.61 -13 -11 c -7.86 -5.73 -15.83 -11.05 -24 -16 c -2.79 -1.69 -6.3 -2.38 -9 -4 c -2.14 -1.28 -3.91 -3.88 -6 -5 c -1.95 -1.05 -4.59 -1.4 -7 -2 c -1.69 -0.42 -3.44 -1 -5 -1 c -1.56 0 -3.66 0.19 -5 1 c -10.4 6.29 -22.47 14.1 -33 22 c -5.45 4.09 -9.76 10.12 -15 14 l -12 6\"/></svg>");
    	String m="<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?><!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\" \"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\"><svg xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\" width=\"456\" height=\"132\"><path fill=\"none\" stroke=\"#000000\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\" d=\"M 2 44 c -0.02 0.19 -1.72 7.99 -1 11 c 0.76 3.17 3.72 7.15 6 10 c 1.53 1.91 3.86 3.53 6 5 c 3.2 2.2 6.51 4.45 10 6 c 5.4 2.4 11.31 3.69 17 6 c 6.92 2.81 13.08 6.44 20 9 c 8.58 3.17 17.02 5.98 26 8 c 27.27 6.12 53.42 11.36 81 16 c 10.73 1.8 21.12 1.57 32 3 c 9.96 1.31 18.94 3.55 29 5 c 21.04 3.04 40.39 7 61 8 c 34.85 1.69 69.52 0.59 104 0 c 4.03 -0.07 7.97 -1.12 12 -2 c 3.77 -0.82 7.42 -1.75 11 -3 c 3.1 -1.08 6.13 -2.39 9 -4 c 5.5 -3.08 11.74 -6.06 16 -10 c 4.2 -3.89 7.74 -9.98 11 -15 c 0.94 -1.45 1.43 -3.29 2 -5 c 0.44 -1.31 1 -2.75 1 -4 c 0 -1.85 -0.12 -4.39 -1 -6 c -2.8 -5.14 -6.49 -11.97 -11 -16 c -10.32 -9.23 -23.9 -16.86 -36 -26 c -4.64 -3.5 -8.36 -7.61 -13 -11 c -7.86 -5.73 -15.83 -11.05 -24 -16 c -2.79 -1.69 -6.3 -2.38 -9 -4 c -2.14 -1.28 -3.91 -3.88 -6 -5 c -1.95 -1.05 -4.59 -1.4 -7 -2 c -1.69 -0.42 -3.44 -1 -5 -1 c -1.56 0 -3.66 0.19 -5 1 c -10.4 6.29 -22.47 14.1 -33 22 c -5.45 4.09 -9.76 10.12 -15 14 l -12 6\"/></svg>";
    	//<?xml version="1.0" encoding="UTF-8" standalone="no"?><!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"><svg xmlns="http://www.w3.org/2000/svg" version="1.1" width="456" height="132"><path fill="none" stroke="#000000" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" d="M 2 44 c -0.02 0.19 -1.72 7.99 -1 11 c 0.76 3.17 3.72 7.15 6 10 c 1.53 1.91 3.86 3.53 6 5 c 3.2 2.2 6.51 4.45 10 6 c 5.4 2.4 11.31 3.69 17 6 c 6.92 2.81 13.08 6.44 20 9 c 8.58 3.17 17.02 5.98 26 8 c 27.27 6.12 53.42 11.36 81 16 c 10.73 1.8 21.12 1.57 32 3 c 9.96 1.31 18.94 3.55 29 5 c 21.04 3.04 40.39 7 61 8 c 34.85 1.69 69.52 0.59 104 0 c 4.03 -0.07 7.97 -1.12 12 -2 c 3.77 -0.82 7.42 -1.75 11 -3 c 3.1 -1.08 6.13 -2.39 9 -4 c 5.5 -3.08 11.74 -6.06 16 -10 c 4.2 -3.89 7.74 -9.98 11 -15 c 0.94 -1.45 1.43 -3.29 2 -5 c 0.44 -1.31 1 -2.75 1 -4 c 0 -1.85 -0.12 -4.39 -1 -6 c -2.8 -5.14 -6.49 -11.97 -11 -16 c -10.32 -9.23 -23.9 -16.86 -36 -26 c -4.64 -3.5 -8.36 -7.61 -13 -11 c -7.86 -5.73 -15.83 -11.05 -24 -16 c -2.79 -1.69 -6.3 -2.38 -9 -4 c -2.14 -1.28 -3.91 -3.88 -6 -5 c -1.95 -1.05 -4.59 -1.4 -7 -2 c -1.69 -0.42 -3.44 -1 -5 -1 c -1.56 0 -3.66 0.19 -5 1 c -10.4 6.29 -22.47 14.1 -33 22 c -5.45 4.09 -9.76 10.12 -15 14 l -12 6"/></svg>
    	//<?xml version= "1.0 " encoding= "UTF-8 " standalone= "no "?><!DOCTYPE svg PUBLIC  "-//W3C//DTD SVG 1.1//EN "  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd "><svg xmlns= "http://www.w3.org/2000/svg " version= "1.1 " width= "452 " height= "68 "><path fill= "none " stroke= "#000000 " stroke-width= "2 " stroke-linecap= "round " stroke-linejoin= "round " d= "M 1 1 c 0.39 0.3 14.23 11.67 22 17 c 10.55 7.23 20.85 14.18 32 20 c 11.91 6.21 24.32 10.98 37 16 c 5.27 2.09 10.45 3.52 16 5 c 9.88 2.63 19.3 5.35 29 7 c 5.86 1 11.8 0.92 18 1 c 20.97 0.27 40.16 0.47 61 0 c 9.25 -0.21 17.89 -0.86 27 -2 c 9.91 -1.24 19.3 -2.79 29 -5 c 9.6 -2.19 18.99 -4.56 28 -8 c 9.27 -3.54 17.58 -8.96 27 -13 c 14.53 -6.23 32.65 -16.83 43 -17 c 5.23 -0.09 11.29 11.28 17 16 c 1.64 1.36 3.98 2.27 6 3 c 1.54 0.56 3.33 0.93 5 1 c 6.55 0.26 13.96 1.31 20 0 c 8.41 -1.83 17.84 -6.29 26 -10 l 7 -5 "/></svg>
    	/*try {
			convertToPng(sb.toString(), "e:/hr.png");
		} catch (Exception e) {
			e.printStackTrace();
		}*/
   	String s="=\\\"=";
   	System.out.println(s.indexOf("/"));
   	s=s.replaceAll("\\", "*");
    	System.out.println(s);
	}
}

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