Here you can find the source of encodeFile(String filePath)
public static String encodeFile(String filePath) throws Exception
//package com.java2s; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.FileInputStream; import android.util.Base64; public class Main { private static final int CACHE_SIZE = 1024; public static String encodeFile(String filePath) throws Exception { byte[] bytes = fileToByte(filePath); return encode(bytes); }// ww w. j ava 2s . co m public static byte[] fileToByte(String filePath) throws Exception { byte[] data = new byte[0]; File file = new File(filePath); if (file.exists()) { FileInputStream in = new FileInputStream(file); ByteArrayOutputStream out = new ByteArrayOutputStream(2048); byte[] cache = new byte[CACHE_SIZE]; int nRead = 0; while ((nRead = in.read(cache)) != -1) { out.write(cache, 0, nRead); out.flush(); } out.close(); in.close(); data = out.toByteArray(); } return data; } public static String encode(byte[] bytes) throws Exception { return new String(Base64.encode(bytes, Base64.DEFAULT)); } }