package com.bumptech.glide.volley;
import android.util.Log;
import com.android.volley.Cache;
import com.android.volley.toolbox.ByteArrayPool;
import com.android.volley.toolbox.DiskBasedCache;
import com.android.volley.toolbox.PoolingByteArrayOutputStream;
import com.bumptech.glide.load.engine.cache.StringKey;
import com.bumptech.glide.load.engine.cache.DiskCache;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
/**
* Closely based on {@link DiskBasedCache}.
*/
public class VolleyDiskCacheWrapper implements Cache {
private static final String TAG = "VolleyDiskCacheWrapper";
/** Magic number for current version of cache file format. */
private static final int CACHE_MAGIC = 0x20120504;
// 2 mb.
private static final int BYTE_POOL_SIZE = 2 * 1024 * 1024;
// 8 kb.
private static final int DEFAULT_BYTE_ARRAY_SIZE = 8 * 1024;
private final DiskCache diskCache;
private final ByteArrayPool byteArrayPool;
public VolleyDiskCacheWrapper(DiskCache diskCache) {
this.diskCache = diskCache;
this.byteArrayPool = new ByteArrayPool(BYTE_POOL_SIZE);
}
@Override
public Entry get(String key) {
InputStream result = diskCache.get(new StringKey(key));
if (result == null) {
return null;
}
try {
CacheHeader header = readHeader(result);
byte[] data = streamToBytes(result);
return header.toCacheEntry(data);
} catch (IOException e) {
if (Log.isLoggable(TAG, Log.DEBUG)) {
e.printStackTrace();
}
diskCache.delete(new StringKey(key));
} finally {
try {
result.close();
} catch (IOException e) { }
}
return null;
}
@Override
public void put(final String key, final Entry entry) {
diskCache.put(new StringKey(key), new DiskCache.Writer() {
@Override
public boolean write(OutputStream os) {
CacheHeader header = new CacheHeader(key, entry);
boolean success = header.writeHeader(os);
if (success) {
try {
os.write(entry.data);
} catch (IOException e) {
success = false;
if (Log.isLoggable(TAG, Log.DEBUG)) {
Log.d(TAG, "Unable to write data", e);
}
}
}
return success;
}
});
}
@Override
public void initialize() { }
@Override
public void invalidate(String key, boolean fullExpire) {
Entry entry = get(key);
if (entry != null) {
entry.softTtl = 0;
if (fullExpire) {
entry.ttl = 0;
}
put(key, entry);
}
}
@Override
public void remove(String key) {
diskCache.delete(new StringKey(key));
}
@Override
public void clear() { }
/**
* Reads the header off of an InputStream and returns a CacheHeader object.
* @param is The InputStream to read from.
* @throws IOException
*/
public CacheHeader readHeader(InputStream is) throws IOException {
CacheHeader entry = new CacheHeader();
int magic = readInt(is);
if (magic != CACHE_MAGIC) {
// don't bother deleting, it'll get pruned eventually
throw new IOException();
}
entry.key = readString(is);
entry.etag = readString(is);
if (entry.etag.equals("")) {
entry.etag = null;
}
entry.serverDate = readLong(is);
entry.ttl = readLong(is);
entry.softTtl = readLong(is);
entry.responseHeaders = readStringStringMap(is);
return entry;
}
/**
* Handles holding onto the cache headers for an entry.
*/
// Visible for testing.
class CacheHeader {
/** The size of the data identified by this CacheHeader. (This is not
* serialized to disk. */
public long size;
/** The key that identifies the cache entry. */
public String key;
/** ETag for cache coherence. */
public String etag;
/** Date of this response as reported by the server. */
public long serverDate;
/** TTL for this record. */
public long ttl;
/** Soft TTL for this record. */
public long softTtl;
/** Headers from the response resulting in this cache entry. */
public Map<String, String> responseHeaders;
private CacheHeader() { }
/**
* Instantiates a new CacheHeader object
* @param key The key that identifies the cache entry
* @param entry The cache entry.
*/
public CacheHeader(String key, Entry entry) {
this.key = key;
this.size = entry.data.length;
this.etag = entry.etag;
this.serverDate = entry.serverDate;
this.ttl = entry.ttl;
this.softTtl = entry.softTtl;
this.responseHeaders = entry.responseHeaders;
}
/**
* Creates a cache entry for the specified data.
*/
public Entry toCacheEntry(byte[] data) {
Entry e = new Entry();
e.data = data;
e.etag = etag;
e.serverDate = serverDate;
e.ttl = ttl;
e.softTtl = softTtl;
e.responseHeaders = responseHeaders;
return e;
}
/**
* Writes the contents of this CacheHeader to the specified OutputStream.
*/
public boolean writeHeader(OutputStream os) {
try {
writeInt(os, CACHE_MAGIC);
writeString(os, key);
writeString(os, etag == null ? "" : etag);
writeLong(os, serverDate);
writeLong(os, ttl);
writeLong(os, softTtl);
writeStringStringMap(responseHeaders, os);
os.flush();
return true;
} catch (IOException e) {
if (Log.isLoggable(TAG, Log.DEBUG)) {
Log.d("%s", e.toString());
}
return false;
}
}
}
/*
* Homebrewed simple serialization system used for reading and writing cache
* headers on disk. Once upon a time, this used the standard Java
* Object{Input,Output}Stream, but the default implementation relies heavily
* on reflection (even for standard types) and generates a ton of garbage.
*/
/**
* Simple wrapper around {@link InputStream#read()} that throws EOFException
* instead of returning -1.
*/
private static int read(InputStream is) throws IOException {
int b = is.read();
if (b == -1) {
throw new EOFException();
}
return b;
}
static void writeInt(OutputStream os, int n) throws IOException {
os.write((n >> 0) & 0xff);
os.write((n >> 8) & 0xff);
os.write((n >> 16) & 0xff);
os.write((n >> 24) & 0xff);
}
static int readInt(InputStream is) throws IOException {
int n = 0;
n |= (read(is) << 0);
n |= (read(is) << 8);
n |= (read(is) << 16);
n |= (read(is) << 24);
return n;
}
static void writeLong(OutputStream os, long n) throws IOException {
os.write((byte)(n >>> 0));
os.write((byte)(n >>> 8));
os.write((byte)(n >>> 16));
os.write((byte)(n >>> 24));
os.write((byte)(n >>> 32));
os.write((byte)(n >>> 40));
os.write((byte)(n >>> 48));
os.write((byte)(n >>> 56));
}
static long readLong(InputStream is) throws IOException {
long n = 0;
n |= ((read(is) & 0xFFL) << 0);
n |= ((read(is) & 0xFFL) << 8);
n |= ((read(is) & 0xFFL) << 16);
n |= ((read(is) & 0xFFL) << 24);
n |= ((read(is) & 0xFFL) << 32);
n |= ((read(is) & 0xFFL) << 40);
n |= ((read(is) & 0xFFL) << 48);
n |= ((read(is) & 0xFFL) << 56);
return n;
}
static void writeString(OutputStream os, String s) throws IOException {
byte[] b = s.getBytes("UTF-8");
writeLong(os, b.length);
os.write(b, 0, b.length);
}
String readString(InputStream is) throws IOException {
int n = (int) readLong(is);
byte[] b = streamToBytes(is, n, byteArrayPool.getBuf(n));
String result = new String(b, "UTF-8");
byteArrayPool.returnBuf(b);
return result;
}
static void writeStringStringMap(Map<String, String> map, OutputStream os) throws IOException {
if (map != null) {
writeInt(os, map.size());
for (Map.Entry<String, String> entry : map.entrySet()) {
writeString(os, entry.getKey());
writeString(os, entry.getValue());
}
} else {
writeInt(os, 0);
}
}
Map<String, String> readStringStringMap(InputStream is) throws IOException {
int size = readInt(is);
Map<String, String> result = (size == 0)
? Collections.<String, String>emptyMap()
: new HashMap<String, String>(size);
for (int i = 0; i < size; i++) {
String key = readString(is).intern();
String value = readString(is).intern();
result.put(key, value);
}
return result;
}
/**
* Reads the contents of an InputStream into a byte[].
*/
private static byte[] streamToBytes(InputStream in, int length, byte[] bytes) throws IOException {
int count;
int pos = 0;
while (pos < length && ((count = in.read(bytes, pos, length - pos)) != -1)) {
pos += count;
}
if (pos != length) {
throw new IOException("Expected " + length + " bytes, read " + pos + " bytes");
}
return bytes;
}
private byte[] streamToBytes(InputStream in) throws IOException {
PoolingByteArrayOutputStream outputStream = new PoolingByteArrayOutputStream(byteArrayPool);
byte[] bytes = byteArrayPool.getBuf(DEFAULT_BYTE_ARRAY_SIZE);
int pos = 0;
while ((in.read(bytes, pos, bytes.length - pos)) != -1) {
outputStream.write(bytes);
}
byteArrayPool.returnBuf(bytes);
byte[] result = outputStream.toByteArray();
outputStream.close();
return result;
}
}