缓存工具类ACache使用方法详解

缓存工具类ACache使用方法详解

本文实例为大家分享了缓存工具类ACache的使用，供大家参考，具体内容如下

(1). ACache mCache = ACache.get(this);

(2). String cacheData = mCache.getAsString("cache_data");

(3). if (!TextUtils.isEmpty(cacheData)) {

                解析、setAdapter、

          }

(4). 然后仍然请求网络，因为缓存的意义是为了在没网的情况下有数据显示。

(5). 网络请求后获得的数据再

mCache.remove("cache_data");

mCache.put("cache_data", data);

Acache.java:

/**

* Copyright (c) 2012-2013, Michael Yang 杨福海 (yangfuhai.com).

*

* Licensed under the Apache License, Version 2.0 (the "License");

* you may not use this file except in compliance with the License.

* You may obtain a copy of the License at

*

* http://apache.org/licenses/LICENSE-2.0

*

* Unless required by applicable law or agreed to in writing, software

* distributed under the License is distributed on an "AS IS" BASIS,

* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

* See the License for the specific language governing permissions and

* limitations under the License.

*/

package com.monkey.monkeymushroom.utils;

import java.io.BufferedReader;

import java.io.BufferedWriter;

import java.io.ByteArrayInputStream;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.FileOutputStream;

import java.io.FileReader;

import java.io.FileWriter;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

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;

import org.json.JSONArray;

import org.json.JSONObject;

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;

/**

* @author Michael Yang（yangfuhai.com） update at 2013.08.07

*/

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 * 100; // 100 mb-->原来50M

private static final int MAX_COUNT = Integer.MAX_VALUE; // 不限制存放数据的数量

private static Map mInstanceMap = new HashMap();

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 getKx(Context ctx, String cacheName) {

String kxDir = ctx.getFilesDir().getAbsolutePath() + "/KxDir";

File f = new File(kxDir, 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);

}

// =======================================

// ============ 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);

}

}

/**

* 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();

}

/**

* @author 杨福海（michael） yangfuhai.com

* @version 1.0

* @title 缓存管理器

*/

public class ACacheManager {

private final AtomicLong cacheSize;

private final AtomicInteger cacheCount;

private final long sizeLimit;

private final int countLimit;

private final Map lastUsageDates = Collections.synchronizedMap(new HashMap());

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> entries = lastUsageDates.entrySet();

synchronized (lastUsageDates) {

for (Entry 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();

}

}

/**

* @author 杨福海（michael） yangfuhai.com

* @version 1.0

* @title 时间计算工具类

*/

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;

}

return new BitmapDrawable(bm);

}

}

}

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