文本文件编码探测,并转码为utf8

jodconverter-web/src/main/java/com/yudianbank/utils/DownloadUtils.java

@@ -5,6 +5,7 @@ import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Component;
 import java.io.*;
 import java.net.*;
+import java.nio.charset.Charset;
 import java.util.UUID;
 
 /**
@@ -71,6 +72,10 @@ public class DownloadUtils {
             response.setContent(realPath);
             // 同样针对类txt文件，如果成功msg包含的是转换后的文件名
             response.setMsg(fileName);
+
+            // 转换文件编码为utf8
+          convertTextPlainFileCharsetToUtf8(realPath);
+
             return response;
         } catch (IOException e) {
             e.printStackTrace();
@@ -152,4 +157,40 @@ public class DownloadUtils {
         }
         return newType;
     }
+
+  /**
+   * 转换文本文件编码为utf8
+   * 探测源文件编码,探测到编码切不为utf8则进行转码
+   * @param filePath 文件路径
+   */
+  private static void convertTextPlainFileCharsetToUtf8(String filePath) throws IOException {
+    File sourceFile = new File(filePath);
+    if(sourceFile.exists() && sourceFile.isFile() && sourceFile.canRead()) {
+      String encoding = null;
+      try {
+        FileCharsetDetector.Observer observer = FileCharsetDetector.guessFileEncoding(sourceFile);
+        encoding = observer.getEncoding();
+      } catch (IOException e) {
+        // 编码探测失败,
+        e.printStackTrace();
+      }
+      if(encoding != null && !"UTF-8".equals(encoding)){
+        // 不为utf8,进行转码
+        File tmpUtf8File = new File(filePath+".utf8");
+        Writer writer = new OutputStreamWriter(new FileOutputStream(tmpUtf8File),"UTF-8");
+        Reader reader = new BufferedReader(new InputStreamReader(new FileInputStream(sourceFile),encoding));
+        char[] buf = new char[1024];
+        int read;
+        while ((read = reader.read(buf)) > 0){
+          writer.write(buf, 0, read);
+        }
+        reader.close();
+        writer.close();
+        // 删除源文件
+        sourceFile.delete();
+        // 重命名
+        tmpUtf8File.renameTo(sourceFile);
+      }
+    }
+  }
 }

jodconverter-web/src/main/java/com/yudianbank/utils/FileCharsetDetector.java

@@ -0,0 +1,157 @@
+package com.yudianbank.utils;
+
+import java.io.BufferedInputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+
+import org.mozilla.intl.chardet.nsDetector;
+import org.mozilla.intl.chardet.nsICharsetDetectionObserver;
+
+/**
+ * 文本文件编码探测工具类
+ *
+ * @author HWliao
+ * @date 2017-12-24
+ */
+public class FileCharsetDetector {
+
+  /**
+   * 传入一个文件(File)对象，检查文件编码
+   *
+   * @param file File对象实例
+   * @return 文件编码，若无，则返回null
+   * @throws FileNotFoundException
+   * @throws IOException
+   */
+  public static Observer guessFileEncoding(File file)
+      throws FileNotFoundException, IOException {
+    return guessFileEncoding(file, new nsDetector());
+  }
+
+  /**
+   * <pre>
+   * 获取文件的编码
+   * @param file
+   *            File对象实例
+   * @param languageHint
+   *            语言提示区域代码 @see #nsPSMDetector ,取值如下：
+   *             1 : Japanese
+   *             2 : Chinese
+   *             3 : Simplified Chinese
+   *             4 : Traditional Chinese
+   *             5 : Korean
+   *             6 : Dont know(default)
+   * </pre>
+   *
+   * @return 文件编码，eg：UTF-8,GBK,GB2312形式(不确定的时候，返回可能的字符编码序列)；若无，则返回null
+   * @throws FileNotFoundException
+   * @throws IOException
+   */
+  public static Observer guessFileEncoding(File file, int languageHint)
+      throws FileNotFoundException, IOException {
+    return guessFileEncoding(file, new nsDetector(languageHint));
+  }
+
+  /**
+   * 获取文件的编码
+   *
+   * @param file
+   * @param det
+   * @return
+   * @throws FileNotFoundException
+   * @throws IOException
+   */
+  private static Observer guessFileEncoding(File file, nsDetector det)
+      throws FileNotFoundException, IOException {
+    // new Observer
+    Observer observer = new Observer();
+    // set Observer
+    // The Notify() will be called when a matching charset is found.
+    det.Init(observer);
+
+    BufferedInputStream imp = new BufferedInputStream(new FileInputStream(
+        file));
+    byte[] buf = new byte[1024];
+    int len;
+    boolean done = false;
+    boolean isAscii = false;
+
+    while ((len = imp.read(buf, 0, buf.length)) != -1) {
+      // Check if the stream is only ascii.
+      isAscii = det.isAscii(buf, len);
+      if (isAscii) {
+        break;
+      }
+      // DoIt if non-ascii and not done yet.
+      done = det.DoIt(buf, len, false);
+      if (done) {
+        break;
+      }
+    }
+    imp.close();
+    det.DataEnd();
+
+    if (isAscii) {
+      observer.encoding = "ASCII";
+      observer.found = true;
+    }
+
+    if (!observer.isFound()) {
+      String[] prob = det.getProbableCharsets();
+      // // 这里将可能的字符集组合起来返回
+      // for (int i = 0; i < prob.length; i++) {
+      // if (i == 0) {
+      // encoding = prob[i];
+      // } else {
+      // encoding += "," + prob[i];
+      // }
+      // }
+      if (prob.length > 0) {
+        // 在没有发现情况下,去第一个可能的编码
+        observer.encoding = prob[0];
+      } else {
+        observer.encoding = null;
+      }
+    }
+    return observer;
+  }
+
+  /**
+   * @author liaohongwei
+   * @Description: 文件字符编码观察者, 但判断出字符编码时候调用
+   * @date 2016年6月20日 下午2:27:06
+   */
+  public static class Observer implements nsICharsetDetectionObserver {
+
+    /**
+     * @Fields encoding : 字符编码
+     */
+    private String encoding = null;
+    /**
+     * @Fields found : 是否找到字符集
+     */
+    private boolean found = false;
+
+    @Override
+    public void Notify(String charset) {
+      this.encoding = charset;
+      this.found = true;
+    }
+
+    public String getEncoding() {
+      return encoding;
+    }
+
+    public boolean isFound() {
+      return found;
+    }
+
+    @Override
+    public String toString() {
+      return "Observer [encoding=" + encoding + ", found=" + found + "]";
+    }
+  }
+
+}