Java自动根据文件内容的编码来读取避免乱码

　通过cpdetector这个开源的jar包可以自动判断当前文件的内容编码，从而在读取的时候选择正确的编码读取，避免乱码问题。

import info.monitorenter.cpdetector.io.ASCIIDetector;
import info.monitorenter.cpdetector.io.CodepageDetectorProxy;
import info.monitorenter.cpdetector.io.JChardetFacade;
import info.monitorenter.cpdetector.io.ParsingDetector;
import info.monitorenter.cpdetector.io.UnicodeDetector;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStreamReader;
public class Main {
public static String getContent(String path) throws Exception {
File file = new File(path);
CodepageDetectorProxy detector = CodepageDetectorProxy.getInstance();
detector.add(new ParsingDetector(false));
detector.add(JChardetFacade.getInstance());
detector.add(ASCIIDetector.getInstance());
detector.add(UnicodeDetector.getInstance());
java.nio.charset.Charset charset = null;
try {
charset = detector.detectCodepage(file.toURI().toURL());
} catch (Exception ex) {
ex.printStackTrace();
}
String charsetName = null;
if (charset != null) {
charsetName = charset.name();
} else {
charsetName = "UTF-8";
}
BufferedReader reader = new BufferedReader(new InputStreamReader(
new FileInputStream(file), charsetName));
String line = null;
String lines = "";
while ((line = reader.readLine()) != null) {
lines += line + "\n";
}
reader.close();
return lines;
}
public static void main(String[] args) throws Exception {
System.out.println(getContent("bin/gbk.txt"));
System.out.println(getContent("bin/utf8.txt"));
}
}