FileUtil.java

package com.gzsll.hupu.util;

import android.content.Context;
import android.content.res.AssetManager;
import android.os.Environment;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

/**
 * Created by sll on 2015/3/7.
 */
public class FileUtil {

    public static boolean hasSDCard() {
        boolean mHasSDcard = false;
        if (Environment.MEDIA_MOUNTED.endsWith(Environment.getExternalStorageState())) {
            mHasSDcard = true;
        } else {
            mHasSDcard = false;
        }

        return mHasSDcard;
    }

    public static String getSdcardPath() {

        if (hasSDCard()) return Environment.getExternalStorageDirectory().getAbsolutePath();

        return "/sdcard/";
    }

    public static void chmod(String permission, String path) {
        try {
            String command = "chmod " + permission + " " + path;
            Runtime runtime = Runtime.getRuntime();
            runtime.exec(command);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static String stringFromAssetsFile(Context context, String fileName) {
        AssetManager manager = context.getAssets();
        InputStream file;
        try {
            file = manager.open(fileName);
            byte[] data = new byte[file.available()];
            file.read(data);
            file.close();
            return new String(data);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 复制assets文件到指定目录
     *
     * @param fileName 文件名
     * @param filePath 目录
     */
    public static void copyAssets(Context context, String fileName, String filePath) {
        InputStream inputStream;
        try {
            inputStream = context.getResources().getAssets().open(fileName);// assets文件夹下的文件
            File file = new File(filePath);
            if (!file.exists()) {
                file.mkdirs();
            }
            FileOutputStream fileOutputStream =
                    new FileOutputStream(filePath + "/" + fileName);// 保存到本地的文件夹下的文件
            byte[] buffer = new byte[1024];
            int count = 0;
            while ((count = inputStream.read(buffer)) > 0) {
                fileOutputStream.write(buffer, 0, count);
            }
            fileOutputStream.flush();
            fileOutputStream.close();
            inputStream.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public boolean copy(File oldFile, File newFile) {
        if (!oldFile.exists()) {
            return false;
        }
        FileInputStream inputStream = null;
        FileOutputStream outputStream = null;
        try {
            inputStream = new FileInputStream(oldFile);
            outputStream = new FileOutputStream(newFile);
            byte[] buffer = new byte[4096];
            while (inputStream.read(buffer) != -1) {
                outputStream.write(buffer);
            }
            return true;
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        } finally {
            try {
                if (inputStream != null) {
                    inputStream.close();
                }
                if (outputStream != null) {
                    outputStream.close();
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    public static boolean exist(String url) {
        File file = new File(url);
        return file.exists();
    }
}