Using freemarker to save the ecrats picture to word

In a business in an existing field, it is often necessary to make statistics on a kind of data, generate echarts charts and export them with corresponding description materials:

• Save eckarts locally

• java reads pictures for base64 encoding

• Making freemarker templates

• Fill freemarker template

• Download word

Save eckarts locally

Use js to send the corresponding request:

                //Let the picture load for a while
                setTimeout(exportImage, 2000);  
                function exportImage(){  
                    var data = "a="+encodeURIComponent(myChart.getDataURL("png"));  
                    var xmlhttp;  
                    if (window.XMLHttpRequest) { // code for IE7+, Firefox, Chrome, Opera, Safari  
                        xmlhttp = new XMLHttpRequest();  
                    } else { // code for IE6, IE5  
                        xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");  
                    }  
                    xmlhttp.open("POST","<%=path%>/servlet/saveImage",true);  
                    xmlhttp.setRequestHeader("Content-type","application/x-www-form-urlencoded");  
                    xmlhttp.onreadystatechange = function() {  
                        if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {  
                            alert("Save successfully");  
                        }  
                    }  
                    xmlhttp.send(data);  
                }  

            }  
        );  

The java code is as follows:

String a = request.getParameter("a");  
        try {  
            String[] url = a.split(",");  
            String u = url[1];  
            // Base64 decoding  
            byte[] b = new BASE64Decoder().decodeBuffer(u);  
            WordUtil wordUtil = new WordUtil();  
            String fileStr = wordUtil.saveFile();   
            // Generate pictures  
            OutputStream out = new FileOutputStream(new   File(fileStr+"\\test.png"));  
            out.write(b);  
            out.flush();  
            out.close();  

java reads pictures for base64 encoding

Convert the file to byte array and code base64 as follows

 public String getImageStr(String imgFile) {  
        InputStream in = null;  
        byte[] data = null;  
        try {  
            in = new FileInputStream(imgFile);  
            data = new byte[in.available()];  
            in.read(data);  
            in.close();  
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
        BASE64Encoder encoder = new BASE64Encoder();  
        return encoder.encode(data);  
    }  

Making freemarker templates

It's easy to make freemarker templates. Note the version of word:
The word documents are typeset, pictures and words are fixed. office is used to save word as xml file. Open xml file and ${*} is used to replace words and pictures, save xml and change suffix to ftl.
In this way, our template is ready. Next, we call the tool class to fill the content into the template. The code is as follows:

public class TemplateTool {

    private Configuration configuration = null;

    public TemplateTool(){
        configuration = new Configuration();
        configuration.setDefaultEncoding("utf-8");
    }

    // Parameters: template path, template name, generated file path, data map to be added
    public void createFile(String temPath, String temName, String filePath, Map dataMap){
        configuration.setClassForTemplateLoading(this.getClass(), temPath);
        Template tl = null;

        try{
            tl = configuration.getTemplate(temName);
        }catch (IOException e){
            e.printStackTrace();
        }

        File outFile = new File(filePath);
        Writer out = null;
        try{
            out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(outFile)));
        }catch(FileNotFoundException e1){
            e1.printStackTrace();
        }

        try{
            tl.process(dataMap, out, ObjectWrapper.BEANS_WRAPPER);
            out.flush();
            out.close();
        }catch (TemplateException e){
            e.printStackTrace();
        }catch (IOException e){
            e.printStackTrace();
        }
    }

Here, the word with pictures and texts has been generated. Next, as long as the file download is provided, the function will be realized.