aSimpleCache初识

晚上家里来了一大堆东北亲戚，挺热闹的，生活嘛，肯定不只有写代码
aSimpleCache是一个缓存框架，中国人写的，一种莫名的亲切感，也是第一次使用，希望可以快速学习，对自己有一定的帮助。
github的链接
直接把那个ACache类拖入项目就可以简单的使用了
下面贴出来这个类的代码

package com.feng.asimplecachetest;import android.content.Context;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.graphics.PixelFormat;import android.graphics.drawable.BitmapDrawable;import android.graphics.drawable.Drawable;import org.json.JSONArray;import org.json.JSONObject;import java.io.BufferedReader;import java.io.BufferedWriter;import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.FileReader;import java.io.FileWriter;import java.io.IOException;import java.io.InputStream;import java.io.ObjectInputStream;import java.io.ObjectOutputStream;import java.io.OutputStream;import java.io.RandomAccessFile;import java.io.Serializable;import java.util.Collections;import java.util.HashMap;import java.util.Map;import java.util.Map.Entry;import java.util.Set;import java.util.concurrent.atomic.AtomicInteger;import java.util.concurrent.atomic.AtomicLong;/** * Created by hasee on 2017/6/12. */public class ACache {    public static final int TIME_HOUR = 60 * 60;    public static final int TIME_DAY = TIME_HOUR * 24;    private static final int MAX_SIZE = 1000 * 1000 * 50; // 50 mb    private static final int MAX_COUNT = Integer.MAX_VALUE; // 不限制存放数据的数量    private static Map<String, ACache> mInstanceMap = new HashMap<String, ACache>();    private ACacheManager mCache;    public static ACache get(Context ctx) {        return get(ctx, "ACache");    }    public static ACache get(Context ctx, String cacheName) {        File f = new File(ctx.getCacheDir(), cacheName);        return get(f, MAX_SIZE, MAX_COUNT);    }    public static ACache get(File cacheDir) {        return get(cacheDir, MAX_SIZE, MAX_COUNT);    }    public static ACache get(Context ctx, long max_zise, int max_count) {        File f = new File(ctx.getCacheDir(), "ACache");        return get(f, max_zise, max_count);    }    public static ACache get(File cacheDir, long max_zise, int max_count) {        ACache manager = mInstanceMap.get(cacheDir.getAbsoluteFile() + myPid());        if (manager == null) {            manager = new ACache(cacheDir, max_zise, max_count);            mInstanceMap.put(cacheDir.getAbsolutePath() + myPid(), manager);        }        return manager;    }    private static String myPid() {        return "_" + android.os.Process.myPid();    }    private ACache(File cacheDir, long max_size, int max_count) {        if (!cacheDir.exists() && !cacheDir.mkdirs()) {            throw new RuntimeException("can't make dirs in " + cacheDir.getAbsolutePath());        }        mCache = new ACacheManager(cacheDir, max_size, max_count);    }    /**     * Provides a means to save a cached file before the data are available.     * Since writing about the file is complete, and its close method is called,     * its contents will be registered in the cache. Example of use:     *     * ACache cache = new ACache(this) try { OutputStream stream =     * cache.put("myFileName") stream.write("some bytes".getBytes()); // now     * update cache! stream.close(); } catch(FileNotFoundException e){     * e.printStackTrace() }     */    class xFileOutputStream extends FileOutputStream {        File file;        public xFileOutputStream(File file) throws FileNotFoundException {            super(file);            this.file = file;        }        public void close() throws IOException {            super.close();            mCache.put(file);        }    }// =======================================// ============ String数据 读写 ==============// =======================================    /**     * 保存 String数据 到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的String数据     */    public void put(String key, String value) {        File file = mCache.newFile(key);        BufferedWriter out = null;        try {            out = new BufferedWriter(new FileWriter(file), 1024);            out.write(value);        } catch (IOException e) {            e.printStackTrace();        } finally {            if (out != null) {                try {                    out.flush();                    out.close();                } catch (IOException e) {                    e.printStackTrace();                }            }            mCache.put(file);        }    }    /**     * 保存 String数据 到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的String数据     * @param saveTime     *            保存的时间，单位：秒     */    public void put(String key, String value, int saveTime) {        put(key, Utils.newStringWithDateInfo(saveTime, value));    }    /**     * 读取 String数据     *     * @param key     * @return String 数据     */    public String getAsString(String key) {        File file = mCache.get(key);        if (!file.exists())            return null;        boolean removeFile = false;        BufferedReader in = null;        try {            in = new BufferedReader(new FileReader(file));            String readString = "";            String currentLine;            while ((currentLine = in.readLine()) != null) {                readString += currentLine;            }            if (!Utils.isDue(readString)) {                return Utils.clearDateInfo(readString);            } else {                removeFile = true;                return null;            }        } catch (IOException e) {            e.printStackTrace();            return null;        } finally {            if (in != null) {                try {                    in.close();                } catch (IOException e) {                    e.printStackTrace();                }            }            if (removeFile)                remove(key);        }    }// =======================================// ============= JSONObject 数据 读写 ==============// =======================================    /**     * 保存 JSONObject数据 到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的JSON数据     */    public void put(String key, JSONObject value) {        put(key, value.toString());    }    /**     * 保存 JSONObject数据 到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的JSONObject数据     * @param saveTime     *            保存的时间，单位：秒     */    public void put(String key, JSONObject value, int saveTime) {        put(key, value.toString(), saveTime);    }    /**     * 读取JSONObject数据     *     * @param key     * @return JSONObject数据     */    public JSONObject getAsJSONObject(String key) {        String JSONString = getAsString(key);        try {            JSONObject obj = new JSONObject(JSONString);            return obj;        } catch (Exception e) {            e.printStackTrace();            return null;        }    }// =======================================// ============ JSONArray 数据 读写 =============// =======================================    /**     * 保存 JSONArray数据 到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的JSONArray数据     */    public void put(String key, JSONArray value) {        put(key, value.toString());    }    /**     * 保存 JSONArray数据 到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的JSONArray数据     * @param saveTime     *            保存的时间，单位：秒     */    public void put(String key, JSONArray value, int saveTime) {        put(key, value.toString(), saveTime);    }    /**     * 读取JSONArray数据     *     * @param key     * @return JSONArray数据     */    public JSONArray getAsJSONArray(String key) {        String JSONString = getAsString(key);        try {            JSONArray obj = new JSONArray(JSONString);            return obj;        } catch (Exception e) {            e.printStackTrace();            return null;        }    }// =======================================// ============== byte 数据 读写 =============// =======================================    /**     * 保存 byte数据 到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的数据     */    public void put(String key, byte[] value) {        File file = mCache.newFile(key);        FileOutputStream out = null;        try {            out = new FileOutputStream(file);            out.write(value);        } catch (Exception e) {            e.printStackTrace();        } finally {            if (out != null) {                try {                    out.flush();                    out.close();                } catch (IOException e) {                    e.printStackTrace();                }            }            mCache.put(file);        }    }    /**     * Cache for a stream     *     * @param key     *            the file name.     * @return OutputStream stream for writing data.     * @throws FileNotFoundException     *             if the file can not be created.     */    public OutputStream put(String key) throws FileNotFoundException {        return new xFileOutputStream(mCache.newFile(key));    }    /**     *     * @param key     *            the file name.     * @return (InputStream or null) stream previously saved in cache.     * @throws FileNotFoundException     *             if the file can not be opened     */    public InputStream get(String key) throws FileNotFoundException {        File file = mCache.get(key);        if (!file.exists())            return null;        return new FileInputStream(file);    }    /**     * 保存 byte数据 到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的数据     * @param saveTime     *            保存的时间，单位：秒     */    public void put(String key, byte[] value, int saveTime) {        put(key, Utils.newByteArrayWithDateInfo(saveTime, value));    }    /**     * 获取 byte 数据     *     * @param key     * @return byte 数据     */    public byte[] getAsBinary(String key) {        RandomAccessFile RAFile = null;        boolean removeFile = false;        try {            File file = mCache.get(key);            if (!file.exists())                return null;            RAFile = new RandomAccessFile(file, "r");            byte[] byteArray = new byte[(int) RAFile.length()];            RAFile.read(byteArray);            if (!Utils.isDue(byteArray)) {                return Utils.clearDateInfo(byteArray);            } else {                removeFile = true;                return null;            }        } catch (Exception e) {            e.printStackTrace();            return null;        } finally {            if (RAFile != null) {                try {                    RAFile.close();                } catch (IOException e) {                    e.printStackTrace();                }            }            if (removeFile)                remove(key);        }    }// =======================================// ============= 序列化 数据 读写 ===============// =======================================    /**     * 保存 Serializable数据 到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的value     */    public void put(String key, Serializable value) {        put(key, value, -1);    }    /**     * 保存 Serializable数据到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的value     * @param saveTime     *            保存的时间，单位：秒     */    public void put(String key, Serializable value, int saveTime) {        ByteArrayOutputStream baos = null;        ObjectOutputStream oos = null;        try {            baos = new ByteArrayOutputStream();            oos = new ObjectOutputStream(baos);            oos.writeObject(value);            byte[] data = baos.toByteArray();            if (saveTime != -1) {                put(key, data, saveTime);            } else {                put(key, data);            }        } catch (Exception e) {            e.printStackTrace();        } finally {            try {                oos.close();            } catch (IOException e) {            }        }    }    /**     * 读取 Serializable数据     *     * @param key     * @return Serializable 数据     */    public Object getAsObject(String key) {        byte[] data = getAsBinary(key);        if (data != null) {            ByteArrayInputStream bais = null;            ObjectInputStream ois = null;            try {                bais = new ByteArrayInputStream(data);                ois = new ObjectInputStream(bais);                Object reObject = ois.readObject();                return reObject;            } catch (Exception e) {                e.printStackTrace();                return null;            } finally {                try {                    if (bais != null)                        bais.close();                } catch (IOException e) {                    e.printStackTrace();                }                try {                    if (ois != null)                        ois.close();                } catch (IOException e) {                    e.printStackTrace();                }            }        }        return null;    }// =======================================// ============== bitmap 数据 读写 =============// =======================================    /**     * 保存 bitmap 到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的bitmap数据     */    public void put(String key, Bitmap value) {        put(key, Utils.Bitmap2Bytes(value));    }    /**     * 保存 bitmap 到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的 bitmap 数据     * @param saveTime     *            保存的时间，单位：秒     */    public void put(String key, Bitmap value, int saveTime) {        put(key, Utils.Bitmap2Bytes(value), saveTime);    }    /**     * 读取 bitmap 数据     *     * @param key     * @return bitmap 数据     */    public Bitmap getAsBitmap(String key) {        if (getAsBinary(key) == null) {            return null;        }        return Utils.Bytes2Bimap(getAsBinary(key));    }// =======================================// ============= drawable 数据 读写 =============// =======================================    /**     * 保存 drawable 到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的drawable数据     */    public void put(String key, Drawable value) {        put(key, Utils.drawable2Bitmap(value));    }    /**     * 保存 drawable 到 缓存中     *     * @param key     *            保存的key     * @param value     *            保存的 drawable 数据     * @param saveTime     *            保存的时间，单位：秒     */    public void put(String key, Drawable value, int saveTime) {        put(key, Utils.drawable2Bitmap(value), saveTime);    }    /**     * 读取 Drawable 数据     *     * @param key     * @return Drawable 数据     */    public Drawable getAsDrawable(String key) {        if (getAsBinary(key) == null) {            return null;        }        return Utils.bitmap2Drawable(Utils.Bytes2Bimap(getAsBinary(key)));    }    /**     * 获取缓存文件     *     * @param key     * @return value 缓存的文件     */    public File file(String key) {        File f = mCache.newFile(key);        if (f.exists())            return f;        return null;    }    /**     * 移除某个key     *     * @param key     * @return 是否移除成功     */    public boolean remove(String key) {        return mCache.remove(key);    }    /**     * 清除所有数据     */    public void clear() {        mCache.clear();    }    /**     * @title 缓存管理器     * @author 杨福海（michael） www.yangfuhai.com     * @version 1.0     */    public class ACacheManager {        private final AtomicLong cacheSize;        private final AtomicInteger cacheCount;        private final long sizeLimit;        private final int countLimit;        private final Map<File, Long> lastUsageDates = Collections.synchronizedMap(new HashMap<File, Long>());        protected File cacheDir;        private ACacheManager(File cacheDir, long sizeLimit, int countLimit) {            this.cacheDir = cacheDir;            this.sizeLimit = sizeLimit;            this.countLimit = countLimit;            cacheSize = new AtomicLong();            cacheCount = new AtomicInteger();            calculateCacheSizeAndCacheCount();        }        /**         * 计算 cacheSize和cacheCount         */        private void calculateCacheSizeAndCacheCount() {            new Thread(new Runnable() {                @Override                public void run() {                    int size = 0;                    int count = 0;                    File[] cachedFiles = cacheDir.listFiles();                    if (cachedFiles != null) {                        for (File cachedFile : cachedFiles) {                            size += calculateSize(cachedFile);                            count += 1;                            lastUsageDates.put(cachedFile, cachedFile.lastModified());                        }                        cacheSize.set(size);                        cacheCount.set(count);                    }                }            }).start();        }        private void put(File file) {            int curCacheCount = cacheCount.get();            while (curCacheCount + 1 > countLimit) {                long freedSize = removeNext();                cacheSize.addAndGet(-freedSize);                curCacheCount = cacheCount.addAndGet(-1);            }            cacheCount.addAndGet(1);            long valueSize = calculateSize(file);            long curCacheSize = cacheSize.get();            while (curCacheSize + valueSize > sizeLimit) {                long freedSize = removeNext();                curCacheSize = cacheSize.addAndGet(-freedSize);            }            cacheSize.addAndGet(valueSize);            Long currentTime = System.currentTimeMillis();            file.setLastModified(currentTime);            lastUsageDates.put(file, currentTime);        }        private File get(String key) {            File file = newFile(key);            Long currentTime = System.currentTimeMillis();            file.setLastModified(currentTime);            lastUsageDates.put(file, currentTime);            return file;        }        private File newFile(String key) {            return new File(cacheDir, key.hashCode() + "");        }        private boolean remove(String key) {            File image = get(key);            return image.delete();        }        private void clear() {            lastUsageDates.clear();            cacheSize.set(0);            File[] files = cacheDir.listFiles();            if (files != null) {                for (File f : files) {                    f.delete();                }            }        }        /**         * 移除旧的文件         *         * @return         */        private long removeNext() {            if (lastUsageDates.isEmpty()) {                return 0;            }            Long oldestUsage = null;            File mostLongUsedFile = null;            Set<Entry<File, Long>> entries = lastUsageDates.entrySet();            synchronized (lastUsageDates) {                for (Entry<File, Long> entry : entries) {                    if (mostLongUsedFile == null) {                        mostLongUsedFile = entry.getKey();                        oldestUsage = entry.getValue();                    } else {                        Long lastValueUsage = entry.getValue();                        if (lastValueUsage < oldestUsage) {                            oldestUsage = lastValueUsage;                            mostLongUsedFile = entry.getKey();                        }                    }                }            }            long fileSize = calculateSize(mostLongUsedFile);            if (mostLongUsedFile.delete()) {                lastUsageDates.remove(mostLongUsedFile);            }            return fileSize;        }        private long calculateSize(File file) {            return file.length();        }    }    /**     * @title 时间计算工具类     * @author 杨福海（michael） www.yangfuhai.com     * @version 1.0     */    private static class Utils {        /**         * 判断缓存的String数据是否到期         *         * @param str         * @return true：到期了 false：还没有到期         */        private static boolean isDue(String str) {            return isDue(str.getBytes());        }        /**         * 判断缓存的byte数据是否到期         *         * @param data         * @return true：到期了 false：还没有到期         */        private static boolean isDue(byte[] data) {            String[] strs = getDateInfoFromDate(data);            if (strs != null && strs.length == 2) {                String saveTimeStr = strs[0];                while (saveTimeStr.startsWith("0")) {                    saveTimeStr = saveTimeStr.substring(1, saveTimeStr.length());                }                long saveTime = Long.valueOf(saveTimeStr);                long deleteAfter = Long.valueOf(strs[1]);                if (System.currentTimeMillis() > saveTime + deleteAfter * 1000) {                    return true;                }            }            return false;        }        private static String newStringWithDateInfo(int second, String strInfo) {            return createDateInfo(second) + strInfo;        }        private static byte[] newByteArrayWithDateInfo(int second, byte[] data2) {            byte[] data1 = createDateInfo(second).getBytes();            byte[] retdata = new byte[data1.length + data2.length];            System.arraycopy(data1, 0, retdata, 0, data1.length);            System.arraycopy(data2, 0, retdata, data1.length, data2.length);            return retdata;        }        private static String clearDateInfo(String strInfo) {            if (strInfo != null && hasDateInfo(strInfo.getBytes())) {                strInfo = strInfo.substring(strInfo.indexOf(mSeparator) + 1, strInfo.length());            }            return strInfo;        }        private static byte[] clearDateInfo(byte[] data) {            if (hasDateInfo(data)) {                return copyOfRange(data, indexOf(data, mSeparator) + 1, data.length);            }            return data;        }        private static boolean hasDateInfo(byte[] data) {            return data != null && data.length > 15 && data[13] == '-' && indexOf(data, mSeparator) > 14;        }        private static String[] getDateInfoFromDate(byte[] data) {            if (hasDateInfo(data)) {                String saveDate = new String(copyOfRange(data, 0, 13));                String deleteAfter = new String(copyOfRange(data, 14, indexOf(data, mSeparator)));                return new String[] { saveDate, deleteAfter };            }            return null;        }        private static int indexOf(byte[] data, char c) {            for (int i = 0; i < data.length; i++) {                if (data[i] == c) {                    return i;                }            }            return -1;        }        private static byte[] copyOfRange(byte[] original, int from, int to) {            int newLength = to - from;            if (newLength < 0)                throw new IllegalArgumentException(from + " > " + to);            byte[] copy = new byte[newLength];            System.arraycopy(original, from, copy, 0, Math.min(original.length - from, newLength));            return copy;        }        private static final char mSeparator = ' ';        private static String createDateInfo(int second) {            String currentTime = System.currentTimeMillis() + "";            while (currentTime.length() < 13) {                currentTime = "0" + currentTime;            }            return currentTime + "-" + second + mSeparator;        }        /*        * Bitmap → byte[]        */        private static byte[] Bitmap2Bytes(Bitmap bm) {            if (bm == null) {                return null;            }            ByteArrayOutputStream baos = new ByteArrayOutputStream();            bm.compress(Bitmap.CompressFormat.PNG, 100, baos);            return baos.toByteArray();        }        /*        * byte[] → Bitmap        */        private static Bitmap Bytes2Bimap(byte[] b) {            if (b.length == 0) {                return null;            }            return BitmapFactory.decodeByteArray(b, 0, b.length);        }        /*        * Drawable → Bitmap        */        private static Bitmap drawable2Bitmap(Drawable drawable) {            if (drawable == null) {                return null;            }// 取 drawable 的长宽            int w = drawable.getIntrinsicWidth();            int h = drawable.getIntrinsicHeight();// 取 drawable 的颜色格式            Bitmap.Config config = drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888 : Bitmap.Config.RGB_565;// 建立对应 bitmap            Bitmap bitmap = Bitmap.createBitmap(w, h, config);// 建立对应 bitmap 的画布            Canvas canvas = new Canvas(bitmap);            drawable.setBounds(0, 0, w, h);// 把 drawable 内容画到画布中            drawable.draw(canvas);            return bitmap;        }        /*        * Bitmap → Drawable        */        @SuppressWarnings("deprecation")        private static Drawable bitmap2Drawable(Bitmap bm) {            if (bm == null) {                return null;            }            BitmapDrawable bd=new BitmapDrawable(bm);            bd.setTargetDensity(bm.getDensity());            return new BitmapDrawable(bm);        }    }}

有时间会分析下代码，完成一个简单的demo

public class MainActivity extends Activity {    private Button save_data;    private  Button restore_data;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        save_data=(Button)findViewById(R.id.save_data);        restore_data=(Button)findViewById(R.id.restore_data);        save_data.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                ACache mCache = ACache.get(MainActivity.this);                mCache.put("test_key1", "齐晨");                mCache.put("test_key2", "齐晨", 10);//保存10秒，如果超过10秒去获取这个key，将为null                mCache.put("test_key3", "test value", 2 * ACache.TIME_DAY);//保存两天，如果超过两天去获取这个key，将为null            }        });        restore_data.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                ACache mCache = ACache.get(MainActivity.this);                String value = mCache.getAsString("test_key2");                Log.i("MainActivity",value+"");            }        });    }}

测试缓存存储，并且10S后删除缓存数据

简单的实现了功能，深入学习的会补充