com.ifengxue.http.parser.FilenameInputStream Maven / Gradle / Ivy

/*
 * Copyright 2019 https://www.ifengxue.com
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


package com.ifengxue.http.parser;

import com.ifengxue.http.contract.HttpResponse;
import java.io.Closeable;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;

/**
 * 带文件名的输入流
 */
public class FilenameInputStream implements AutoCloseable, Closeable {

  /**
   * 文件名称
   */
  private final String filename;
  /**
   * 输入流
   */
  private final InputStream stream;

  public static FilenameInputStream from(HttpResponse response) throws IOException {
    String headerValue = response.getHeaderValue("Content-Disposition");
    String filename = parseAttachmentFilename(headerValue);
    return new FilenameInputStream(filename, response.getContent());
  }

  public FilenameInputStream(String filename, InputStream stream) {
    this.filename = filename;
    this.stream = stream;
  }

  public String getFilename() {
    return filename;
  }

  @SuppressWarnings("unused")
  public InputStream getStream() {
    return stream;
  }

  @Override
  public String toString() {
    return "FilenameInputStream{" +
        "filename='" + filename + '\'' +
        ", stream=" + stream +
        '}';
  }

  /**
   * 处理附件的文件名。支持RFC 6266标准
   *    *   Content-Disposition: attachment;filename="encoded_text";filename*=utf-8''encoded_text
   * 
   */
  static String parseAttachmentFilename(String headerValue) throws UnsupportedEncodingException {
    if (headerValue == null) {
      return null;
    }
    String filenameWild = "filename*";
    int filenameWildIndex = headerValue.indexOf(filenameWild);
    if (filenameWildIndex != -1) {
      int lastIndex = headerValue.indexOf(';', filenameWildIndex);
      String substring;
      if (lastIndex == -1) {
        substring = headerValue.substring(filenameWildIndex + filenameWild.length() + 1);
      } else {
        substring = headerValue.substring(filenameWildIndex + filenameWild.length() + 1, lastIndex);
      }
      String[] ary = substring.split("''");
      return URLDecoder.decode(ary[1], ary[0]);
    }
    String filename = "filename";
    int filenameIndex = headerValue.indexOf(filename);
    if (filenameIndex != -1) {
      int lastIndex = headerValue.indexOf(';', filenameIndex);
      String substring;
      // 处理filename=文件名，不包含双引号的情况
      int offset = 2;
      if (headerValue.substring(filenameIndex + filename.length() + 1).charAt(0) != '\"') {
        offset = 1;
      }
      if (lastIndex == -1) {
        substring = headerValue.substring(filenameIndex + filename.length() + offset);
      } else {
        substring = headerValue
            .substring(filenameIndex + filename.length() + offset, offset == 2 ? lastIndex - 1 : lastIndex);
      }
      return URLDecoder.decode(substring, "UTF-8");
    }
    throw new IllegalStateException("Not valid Content-Disposition header: " + headerValue);
  }

  @Override
  public void close() throws IOException {
    if (stream != null) {
      stream.close();
    }
  }
}