package com.hy.util;
im
port java.io.FileInputStream;
im
port java.io.IOException;
im
port java.util.HashMap;
public class FileType {
// 缓存文件头信息-文件头信息
public static final HashMap<String, String> mFileTypes = new HashMap<String, String>();
static {
// images
mFileTypes.put("FFD8FFE0", "jpg");
mFileTypes.put("89504E47", "png");
mFileTypes.put("47494638", "gif");
mFileTypes.put("49492A00", "tif");
mFileTypes.put("424D", "bmp");
//
mFileTypes.put("41433130", "dwg"); // CAD
mFileTypes.put("38425053", "psd");
mFileTypes.put("7B5C727466", "rtf"); // 日记本
mFileTypes.put("CEA2C8ED", "txt");
mFileTypes.put("3C3F786D6C", "xml");
mFileTypes.put("68746D6C3E", "html");
mFileTypes.put("44656C69766572792D646174653A", "eml"); // 邮件
mFileTypes.put("D0CF11E0", "doc");
mFileTypes.put("5374616E64617264204A", "mdb");
mFileTypes.put("252150532D41646F6265", "ps");
mFileTypes.put("255044462D312E", "pdf");
mFileTypes.put("504B0304", "docx");
mFileTypes.put("52617221", "rar");
mFileTypes.put("57415645", "wav");
mFileTypes.put("41564920", "avi");
mFileTypes.put("2E524D46", "rm");
mFileTypes.put("000001BA", "mpg");
mFileTypes.put("000001B3", "mpg");
mFileTypes.put("6D6F6F76", "mov");
mFileTypes.put("3026B2758E66CF11", "asf");
mFileTypes.put("4D546864", "mid");
mFileTypes.put("1F8B08", "gz");
mFileTypes.put("", "");
mFileTypes.put("", "");
}
public static String getFileType(String filePath) {
return mFileTypes.get(getFileHeader(filePath));
}
public static String getFileHeader(String filePath) {
FileInputStream is = null;
String value = null;
try {
is = new FileInputStream(filePath);
byte[] b = new byte[4];
is.read(b, 0, b.length);
value = bytesToHexString(b);
} catch (Exception e) {
} finally {
if (null != is) {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return value;
}
private static String bytesToHexString(byte[] src) {
StringBuilder builder = new StringBuilder();
if (src == null || src.length <= 0) {
return null;
}
String hv;
for (int i = 0; i < src.length; i++) {
// 以十六进制（基数 16）无符号整数形式返回一个整数参数的字符串表示形式，并转换为大写
hv = Integer.toHexString(src[i] & 0
xFF).toUpperCase();
if (hv.length() < 2) {
builder.append(0);
}
builder.append(hv);
}
return builder.toString();
}
public static void main(String[] args) throws Exception {
final String fileType = getFileType("E:/1.java");
System.out.println(fileType);
}
