Java 通过ant打包时给JS/Jsp/css等文件加上版本号 防止有缓存

AddJsAndCssVersion.java

  1 import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.Writer;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.List;

import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.Task;


public class AddJsAndCssVersion extends Task {

    private String path;

    @Override
    public void execute() throws BuildException {
        Date date = new Date();
        SimpleDateFormat df = new SimpleDateFormat("yyyyMMddhhmmss");
        String version = df.format(date);
        addVersion(path, version);
    }

    private void addVersion(String path, String version) {
        File dir = new File(path);
        File[] files = dir.listFiles();
        if (files == null)
            return;
        for (int i = 0; i < files.length; i++) {
            if (files[i].isDirectory()) {
                addVersion(files[i].getAbsolutePath(), version);
            } else {
                String strFileName = files[i].getAbsolutePath().toLowerCase();
                //Add version in HTML/JSP page
                if (strFileName.endsWith(".html") || strFileName.endsWith(".jsp")  ) {
                    System.out.println(strFileName);
                    InputStream is = null;
                    OutputStream os = null;
                    List<String> contentList = new ArrayList<String>();

                    try {
                        is = new FileInputStream(files[i]);
                        Reader r = new InputStreamReader(is);
                        BufferedReader br = new BufferedReader(r);
                        String line = null;
                        while ((line = br.readLine()) != null) {
                            String modLine = getModLine(line, version);
                            if (modLine != null) {
                                line = modLine;
                            }
                            line = line + "
";
                            contentList.add(line);
                        }
                        br.close();
                        r.close();
                    } catch (Exception e) {
                        e.printStackTrace();
                    } finally {
                        if (null != is) {
                            try {
                                is.close();
                            } catch (Exception e) {
                                e.printStackTrace();
                            }
                        }
                    }

                    try {
                        os = new FileOutputStream(files[i]);
                        Writer w = new OutputStreamWriter(os);
                        BufferedWriter bw = new BufferedWriter(w);
                        for (Iterator<String> it = contentList.iterator(); it
                                .hasNext();) {
                            String line = it.next();
                            bw.write(line);
                        }
                        bw.flush();
                        bw.close();
                        w.close();
                    } catch (Exception e) {
                        e.printStackTrace();
                    } finally {
                        if (null != os) {
                            try {
                                os.close();
                            } catch (Exception e) {
                                e.printStackTrace();
                            }
                        }
                    }
                }
            }
        }
    }

    /**
     * Add version number for JS/CSS link.
     * */
    private String getModLine(String line, String version) {
        line.trim();
        if (line.indexOf("<script") !=-1
            && line.indexOf("type="text/javascript") !=-1
            && line.endsWith("</script>")) {

            int pos = line.indexOf(".js");
            String modLine = line.substring(0, pos) + ".js?version=" + version + ""></script>";
            return modLine;

        } else if (line.indexOf("<link ") !=-1
            && line.indexOf("rel="stylesheet"") !=-1
            && line.indexOf("type="text/css"") !=-1
            && ( line.endsWith("/>") || line.endsWith(">"))) {

            int pos = line.indexOf(".css");
            String modLine = line.substring(0, pos) + ".css?version=" + version  + ""/>";
            return modLine;

        } else {
            return null;
        }

    }

    public void setPath(String path) {
        this.path = path;
    }

    public String getPath() {
        return this.path;
    }
}

 达到的效果如下图：

其中build.xml中代码参考上一篇文章，搜索AddJsAndCssVersion。