android 日志文件输出

try {

} catch (Exception e) {
LogUtil.LogException(e);
}

package com.hexun.util;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.RandomAccessFile;
import java.io.StringWriter;

import android.os.Environment;
import android.util.Log;

/**
* 日志打印
*/
public class LogUtil {

private static final String FILE_NAME = "/logs.txt";
private static Boolean MYLOG_SWITCH = true; // 日志文件总开关

public static void i(String tag, String str) {
Log.i(tag, str.toString());
}

public static void LogException(Exception e) {
if (MYLOG_SWITCH) {
StringWriter sw = new StringWriter();
PrintWriter pw = new PrintWriter(sw);
e.printStackTrace(pw);
String str = sw.toString();
writeException(str);
} else {
e.printStackTrace();
}
}

private static void writeException(String content) {
try {
if (Environment.getExternalStorageState().equals(
Environment.MEDIA_MOUNTED)) {
// 获取SD卡的目录
File sdCardDir = Environment.getExternalStorageDirectory();
File targetFile = new File(sdCardDir.getCanonicalPath()
+ FILE_NAME);
// 以指定文件创建RandomAccessFile对象
RandomAccessFile raf = new RandomAccessFile(targetFile, "rw");
// 将文件记录指针移动到最后
raf.seek(targetFile.length());
// 输出文件内容
raf.write(content.getBytes());
raf.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}

private static String readException() {
try {
if (Environment.getExternalStorageState().equals(
Environment.MEDIA_MOUNTED)) {
// 获得SD卡对应的存储目录
File sdCardDir = Environment.getExternalStorageDirectory();
// 获取指定文件对应的输入流
FileInputStream fis = new FileInputStream(
sdCardDir.getCanonicalPath() + FILE_NAME);
// 将指定输入流包装成BufferReader
BufferedReader br = new BufferedReader(new InputStreamReader(
fis));
StringBuilder sb = new StringBuilder("");
String line = null;
// 循环读取文件内容
while ((line = br.readLine()) != null) {
sb.append(line);
}
br.close();
return sb.toString();
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}

}