Android asynchronous image loading method 1 (2)

Filecache. Java is as follows:

Package CN. loadimages; import Java. io. file; import android. content. context; import android.net. uri; import android. OS. environment; public class filecache {private file filecachedir; Public filecache (context) {If (environment. getexternalstoragestate (). equals (environment. media_mounted) {filecachedir = new file (environment. getexternalstoragedirectory (), "ideallv001");} else {// context. getcachedir (); // Obtain the directory of the cached file filecachedir = context. getcachedir ();} If (! Filecachedir. exists () {filecachedir. mkdirs () ;}} public file getimagefile (string URL) {// string filename = string. valueof (URL. hashcode (); // string filename = urlencoder. encode (URL); Uri URI uri = Uri. parse (URL); string filename = Uri. getlastpathsegment (); file = new file (filecachedir, filename); Return file;} public void clear () {file [] files = filecachedir. listfiles (); If (Files = NULL) {return;} For (File file: Files) {file. delete ();}}}

Memorycache. Java is as follows:

Package CN. loadimages; import Java. lang. ref. softreference; import Java. util. collections; import Java. util. hashmap; import Java. util. iterator; import Java. util. linkedhashmap; import Java. util. map; import Java. util. map. entry; import Java. util. concurrent. concurrenthashmap; import android. graphics. bitmap; import android. util. log; public class memorycache {Private Static final string tag = "XX"; public static has Hmap <string, integer> bitmapssizehashmap; // 1 creates a level-1 cache // Note: collections is used. synchronizedmap changes it to a synchronized map private Map <string, bitmap> hardbitmapcachehashmap = collections. synchronizedmap (New linkedhashmap <string, bitmap> (10, 1.5f, true); // 2 create a private final static concurrenthashmap <string, softreference <bitmap> softbitmapcachehashmap = new concurrenthashmap <string, softreference <bitmap> (20); // Level 1 Total cache allocation size private long allocatedmemorymaxsize = 0; // The used size of the first-level cache private long nowtotalusedmemorysize = 0; Public memorycache () {// use 10% of available heap size setallocatedmemorymaxsize (runtime. getruntime (). maxmemory ()/10); // 85 bitmapssizehashmap = new hashmap <string, integer> ();} public void setallocatedmemorymaxsize (long allocatedmemorymaxsize) {This. allocatedmemorymaxsize = allocatedmemorymaxsize; log. I (TAG, "allocatedmemorymaxsize =" + allocatedmemorymaxsize/1024/1024 + "MB");} public bitmap getbitmapfrommemory (string URL) {try {// 1 search for the image Bitmap bitmap = hardbitmapcachehashmap from the first-level cache. get (URL); If (Bitmap! = NULL) {// now that you want to get this image, the image is recently used // that is, it is the latest object in all objects. // remove the object from the hardbitmapcachehashmap first // insert it to the front of the hardbitmapcachehashmap. remove (URL); hardbitmapcachehashmap. put (URL, bitmap); Return bitmap;} // 2 search for the image from the second-level cache // if the image is not in shardbitmapcache, this may be because the object is too old // and the shardbitmapcache capacity has reached the upper limit, so I saved it to softbitmapcachehashmap // so I tried to get the object system from softbitmapcachehashmap. out. println ("88 get method from softreferenc E. Obtain "); system. out. println ("88 get URL obtained from softreference =" + URL); softreference <bitmap> bitmapreference = softbitmapcachehashmap. get (URL); If (bitmapreference! = NULL) {bitmap BP = bitmapreference. Get (); If (BP! = NULL) {return bp;} else {// softreference has been recycled by GC softbitmapcachehashmap. remove (URL) ;}} return NULL;} catch (nullpointerexception ex) {ex. printstacktrace (); return NULL ;}} public void putbitmaptomemory (string URL, Bitmap bitmap) {try {If (! Hardbitmapcachehashmap. containskey (URL) {nowtotalusedmemorysize + = getbitmapsizeinbytes (bitmap, URL); system. out. println ("88 put method nowtotalusedmemorysize =" + nowtotalusedmemorysize); checkmemorysizestatus (); hardbitmapcachehashmap. put (URL, bitmap) ;}} catch (throwable th) {th. printstacktrace () ;}/// check the usage of the level-1 cache // if the level-1 cache has reached the upper limit, put the last element in the cache into the softbitmapcachehashmap of the second-level cache. // Add it to the first-level cache and delete private void checkmemorysizestatus () {int hardbitmapcachehashmapsize = hardbitmapcachehashmap. size (); int COUNT = 0; system. out. println ("88 checksizestatus method nowtotalusedmemorysize =" + nowtotalusedmemorysize); system. out. println ("88 checksizestatus method in the memorymaxsize =" + allocatedmemorymaxsize); If (nowtotalusedmemorysize> = allocatedmemorymaxsize) {system. out. println ("nowtotalusedmemorysize> = memorymaxsize"); system. out. in the println ("88 checksizestatus method, hardbitmapcachehashmap. size () = "+ hardbitmapcachehashmap. size (); iterator <entry <string, bitmap> iter = hardbitmapcachehashmap. entryset (). iterator (); // least recently accessed item will be the first one iterated while (ITER. hasnext () {count ++; entry <string, bitmap> entry = ITER. next (); If (COUNT = hardbitmapcachehashmapsize) {system. out. println ("88 checksizestatus method COUNT =" + count); system. out. println ("88 checksizestatus method in memorymaxsize =" + allocatedmemorymaxsize); system. out. println ("88 checksizestatus: nowtotalusedmemorysize =" + nowtotalusedmemorysize); nowtotalusedmemorysize-= getbitmapsizeinbytes (entry. getvalue (), entry. getkey (); // 1 place the last element in softbitmapcachehashmap. put (entry. getkey (), new softreference <bitmap> (entry. getvalue (); system. out. println ("88 checksizestatus method put in softreference url =" + entry. getkey (); system. out. println ("88 checksizestatus method put in softreference softbitmapcachehashmap. size () = "+ softbitmapcachehashmap. size (); // 2 Delete the last element ITER. remove (); // 3 Delete the bitmapssizehashmap element from bitmapssizehashmap. remove (entry. getkey (); system. out. println ("88 checksizestatus method after deleting hardbitmapcachehashmap. size () = "+ hardbitmapcachehashmap. size (); system. out. println ("88 checksizestatus method after deletion softbitmapcachehashmap. size () = "+ softbitmapcachehashmap. size (); system. out. println ("nowtotalusedmemorysize =" + nowtotalusedmemorysize); system. out. println ("88 checksizestatus method after deletion memorymaxsize =" + allocatedmemorymaxsize) ;}}if (Region >= allocatedmemorymaxsize) {checkmemorysizestatus () ;}} public void clear () {try {hardbitmapcachehashmap. clear (); softbitmapcachehashmap. clear (); bitmapssizehashmap. clear (); nowtotalusedmemorysize = 0;} catch (nullpointerexception ex) {ex. printstacktrace () ;}// obtain the bitmap size long getbitmapsizeinbytes (Bitmap bitmap, string URL) {If (Bitmap = NULL) {return 0;} int bitmapsize = bitmapssizehashmap. get (URL); Return bitmapsize; // return bitmap. getrowbytes () * bitmap. getheight ();}}

Imageloader. Java is as follows:

Package CN. loadimages; import Java. io. file; import Java. io. fileinputstream; import Java. io. fileoutputstream; import Java. io. inputstream; import Java. io. outputstream; import java.net. httpurlconnection; import java.net. URL; import Java. util. collections; import Java. util. map; import Java. util. weakhashmap; import Java. util. concurrent. executorservice; import Java. util. concurrent. executors; import android. app. activit Y; import android. content. context; import android. graphics. bitmap; import android. graphics. bitmapfactory; import android. widget. imageview; import CN. ideallistview. r; public class imageloader {memorycache = new memorycache (); filecache; private Boolean success = false; private final int required_bitmap_width = 50; private final int required_bitmap_height = 50; private final in T required_bitmap_maxnumofpixels = 200*200; // see the document: // weakhashmap is not synchronized like most collection classes. // you can use collections. synchronizedmap method to construct a synchronized weakhashmap private Map <imageview, string> imageviewsweakhashmap = collections. synchronizedmap (New weakhashmap <imageview, string> (); executorservice; // The default image final int defaultimageid = R. drawable. stub; Public imageloader (context) {filecache = new filecache (Co Ntext); // create a thread pool that can reuse a set of fixed threads and run these threads executorservice = executors in a shared unbounded queue. newfixedthreadpool (5);} // display the network image public void displayimage (string URL, imageview) {// 1 put the imageview and its corresponding URL in imageviewsweakhashmap. put (imageview, URL); // 2 tries to get the image Bitmap bitmap = memorycache from the memory. getbitmapfrommemory (URL); If (Bitmap! = NULL) {imageview. setimagebitmap (Bitmap);} // 3 is not in the memory, else {taskqueueforimages (URL, imageview) is obtained from the SD card and network; imageview. setimageresource (defaultimageid) ;}} private void upload (string URL, imageview) {willloadedimagebean = new willloadedimagebean (URL, imageview); // submit a runnable task for execution, return a future executorservice indicating the task. submit (New loaderimagesrunnable (willloade Dimagebean);} // This thread runs class loaderimagesrunnable implements runnable {willloadedimagebean; loaderimagesrunnable (willloadedimagebean) {This. willloadedimagebean = willloadedimagebean;} @ override public void run () {try {If (isimageviewreused (willloadedimagebean) {return ;} // obtain the corresponding Bitmap Based on the image URL // 1 search for it from sdcard // 2 if it is not in sdcard, It is downloaded from the network, save the image to sdcard. // 3. Save the SDC The Bitmap bitmap = getbitmapbyurl (willloadedimagebean. URL); // 4 Save the image to memorycache. putbitmaptomemory (willloadedimagebean. URL, bitmap); If (isimageviewreused (willloadedimagebean) {return;} // 5 display bitmap in the UI bitmapdisplayerrunnableinuithread bitmapdisplayerrunnable = new vertex (bitmap, willloadedimagebean ); activity activity = (activity) willloadedimagebean. I Mageview. getcontext (); activity. runonuithread (bitmapdisplayerrunnable);} catch (throwable th) {th. printstacktrace () ;}}// obtain the corresponding bitmap private bitmap getbitmapbyurl (string URL) through the URL {// 1 obtain file = filecache from the SD card. getimagefile (URL); Bitmap bitmap = getbitmapfromsdcardfile (File); If (Bitmap! = NULL) {return bitmap;} else {// 2 If the SD card does not exist, bitmap = getbitmapfromnetwork (URL, file) is downloaded from the network and saved to the file of the SD card ); if (Bitmap! = NULL) {return bitmap;} return NULL;} private bitmap getbitmapfromsdcardfile (File file) {If (! Isgetbitmapthumbnail) {try {fileinputstream inputstream = new fileinputstream (File); Bitmap bitmap = bitmapfactory. decodestream (inputstream); inputstream. close (); Return bitmap;} catch (exception e) {e. printstacktrace () ;}} else {try {string filepath = file. getabsolutepath (); int minsidelength = math. min (required_bitmap_height, required_bitmap_width); bitmap BP = utils. getbitmapthumbnail (filepath, minsidelengt H, required_bitmap_maxnumofpixels); Return bp;} catch (exception e) {e. printstacktrace () ;}} return NULL;} // Private bitmap getbitmapfromsdcardfile (File file) {// try {// decode image size // bitmapfactory. options options1 = new bitmapfactory. options (); // options1.injustdecodebounds = true; // fileinputstream stream1 = new fileinputstream (File); // bitmapfactory. decodestream (stream1, null, options1); // st Ream1.close (); ///// find the correct scale value. it shoshould be the power of 2. // final int required_size = 70; // int width_tmp = options1.outwidth, height_tmp = options1.outheight; // int scale = 1; // while (true) {// If (width_tmp/2 <required_size | height_tmp/2 <required_size) // break; // width_tmp/= 2; // height_tmp/= 2; // scale * = 2; //} // decode with insamplesize // bitmapfactory. options options2 = new bi Tmapfactory. options (); // options2.insamplesize = scale; // fileinputstream stream2 = new fileinputstream (File); // Bitmap bitmap = bitmapfactory. decodestream (stream2, null, options2); // stream2.close (); // system. out. println ("xxxxxxxxxxxxxxxxx F. getpath = "+ file. getpath (); // system. out. println ("xxxxxxxxxxxxxxxxx options1.outwidth =" + options1.outwidth); // system. out. println ("xxxxxxxxxxxxxxxxx options1.outh Eight = "+ options1.outheight); // system. out. println ("xxxxxxxxxxxxxxxxx scale =" + scale); // return bitmap; //} catch (filenotfoundexception e) {//} // catch (ioexception e) {// E. printstacktrace (); //} // return NULL; // download the image from the network and save it to sdcard private bitmap getbitmapfromnetwork (string URL, file) {try {Bitmap bitmap = NULL; Url imageurl = new URL (URL); httpurlconnection conn = (httpurlconnection) imageu RL. openconnection (); Conn. setconnecttimeout (30000); Conn. setreadtimeouts (30000); Conn. setinstancefollowredirects (true); inputstream is = Conn. getinputstream (); // Save the memorycache size. bitmapssizehashmap. put (URL, Conn. getcontentlength (); outputstream OS = new fileoutputstream (File); utils. copystream (is, OS); OS. close (); bitmap = getbitmapfromsdcardfile (File); Return bitmap;} catch (throwable ex) {ex. prin Tstacktrace (); If (ex instanceof outofmemoryerror) {memorycache. clear ();} return NULL ;}}// display bitmap class implements runnable {Bitmap bitmap; willloadedimagebean; Public evaluate (Bitmap bitmap, willloadedimagebean) in the UI thread) {This. bitmap = bitmap; this. willloadedimagebean = willloadedimagebean;} public Vo Id run () {If (isimageviewreused (willloadedimagebean) {return;} If (Bitmap! = NULL) {willloadedimagebean. imageview. setimagebitmap (Bitmap);} else {willloadedimagebean. imageview. setimageresource (defaultimageid) ;}}// task for the queue private class willloadedimagebean {Public String URL; Public imageview; Public willloadedimagebean (string URL, imageview) {This. url = URL; this. imageview = imageview;} Boolean isimageviewreused (willloadedimagebean willlo Adedimagebean) {string imageurl = imageviewsweakhashmap. Get (willloadedimagebean. imageview); If (imageurl = NULL |! Imageurl. Equals (willloadedimagebean. url) {return true;} return false;} public void merge AchE () {memorycache. Clear (); filecache. Clear ();}}