code perfect

app/src/main/AndroidManifest.xml

@@ -12,7 +12,8 @@
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
         android:theme="@style/AppTheme">
-        <activity android:name=".TestAsyncTaskActivity"></activity>
+        <activity android:name=".bitmap.test.TestCacheActivity"></activity>
+        <activity android:name=".TestAsyncTaskActivity" />
 
         <provider
             android:name=".provider.MyContentProvider"
@@ -53,7 +54,7 @@
         <activity android:name=".HorizontalScrollViewExActivity" />
 
         <service android:name=".service.TestService" />
-        <service android:name=".thread.MyIntentService"/>
+        <service android:name=".thread.MyIntentService" />
     </application>
 
 </manifest>
\ No newline at end of file

app/src/main/java/com/mxdl/customview/MainActivity.java

@@ -11,6 +11,7 @@ import android.view.View;
 import android.widget.Button;
 
 import com.mxdl.customview.bitmap.DiskLruCache;
+import com.mxdl.customview.bitmap.test.TestCacheActivity;
 import com.mxdl.customview.test.MainTestActivity;
 import com.mxdl.customview.thread.MyAsyncTask;
 
@@ -34,6 +35,7 @@ public class MainActivity extends AppCompatActivity implements View.OnClickListe
     private Button mBtnRectCapture;
     private Button mBtnService;
     private Button mBtnAsyncTask;
+    private Button mBtnCache;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -47,6 +49,7 @@ public class MainActivity extends AppCompatActivity implements View.OnClickListe
         mBtnRectCapture = findViewById(R.id.btn_capture_rect);
         mBtnService = findViewById(R.id.btn_service);
         mBtnAsyncTask = findViewById(R.id.btn_async_task);
+        mBtnCache = findViewById(R.id.btn_cache);
 
         mBtnStickyLayout.setOnClickListener(this);
         mBtnHorizontalScrollViewEx.setOnClickListener(this);
@@ -56,12 +59,7 @@ public class MainActivity extends AppCompatActivity implements View.OnClickListe
         mBtnRectCapture.setOnClickListener(this);
         mBtnService.setOnClickListener(this);
         mBtnAsyncTask.setOnClickListener(this);
-
-        final long DISK_CACHE_SIZE = 1024 * 1024 * 50; //50MB
-        File diskCacheDir = getBaseContext().getCacheDir();
-        if (!diskCacheDir.exists()) {
-            diskCacheDir.mkdirs();
-        }
+        mBtnCache.setOnClickListener(this);
 
     }
 
@@ -92,6 +90,9 @@ public class MainActivity extends AppCompatActivity implements View.OnClickListe
             case R.id.btn_async_task:
                 startActivity(new Intent(this, TestAsyncTaskActivity.class));
                 break;
+            case R.id.btn_cache:
+                startActivity(new Intent(this, TestCacheActivity.class));
+                break;
         }
 
 

app/src/main/java/com/mxdl/customview/bitmap/ImageResizer.java

+package com.mxdl.customview.bitmap;
+
+import java.io.FileDescriptor;
+import android.content.res.Resources;
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+import android.util.Log;
+
+public class ImageResizer {
+    private static final String TAG = "ImageResizer";
+
+    public ImageResizer() {
+    }
+
+    public Bitmap decodeSampledBitmapFromResource(Resources res,
+            int resId, int reqWidth, int reqHeight) {
+        // First decode with inJustDecodeBounds=true to check dimensions
+        final BitmapFactory.Options options = new BitmapFactory.Options();
+        options.inJustDecodeBounds = true;
+        BitmapFactory.decodeResource(res, resId, options);
+
+        // Calculate inSampleSize
+        options.inSampleSize = calculateInSampleSize(options, reqWidth,
+                reqHeight);
+
+        // Decode bitmap with inSampleSize set
+        options.inJustDecodeBounds = false;
+        return BitmapFactory.decodeResource(res, resId, options);
+    }
+    public void test(){
+    }
+    public Bitmap decodeSampledBitmapFromFileDescriptor(FileDescriptor fd, int reqWidth, int reqHeight) {
+        // First decode with inJustDecodeBounds=true to check dimensions
+        final BitmapFactory.Options options = new BitmapFactory.Options();
+        options.inJustDecodeBounds = true;
+        BitmapFactory.decodeFileDescriptor(fd, null, options);
+
+        // Calculate inSampleSize
+        options.inSampleSize = calculateInSampleSize(options, reqWidth,
+                reqHeight);
+
+        // Decode bitmap with inSampleSize set
+        options.inJustDecodeBounds = false;
+        return BitmapFactory.decodeFileDescriptor(fd, null, options);
+    }
+
+    public int calculateInSampleSize(BitmapFactory.Options options,
+            int reqWidth, int reqHeight) {
+        if (reqWidth == 0 || reqHeight == 0) {
+            return 1;
+        }
+
+        // Raw height and width of image
+        final int height = options.outHeight;
+        final int width = options.outWidth;
+        Log.d(TAG, "origin, w= " + width + " h=" + height);
+        int inSampleSize = 1;
+
+        if (height > reqHeight || width > reqWidth) {
+            final int halfHeight = height / 2;
+            final int halfWidth = width / 2;
+
+            // Calculate the largest inSampleSize value that is a power of 2 and
+            // keeps both
+            // height and width larger than the requested height and width.
+            while ((halfHeight / inSampleSize) >= reqHeight
+                    && (halfWidth / inSampleSize) >= reqWidth) {
+                inSampleSize *= 2;
+            }
+        }
+
+        Log.d(TAG, "sampleSize:" + inSampleSize);
+        return inSampleSize;
+    }
+}

app/src/main/java/com/mxdl/customview/bitmap/test/Test.java

+package com.mxdl.customview.bitmap.test;
+
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+import android.os.Environment;
+import android.util.Log;
+import android.util.LruCache;
+
+import com.mxdl.customview.bitmap.DiskLruCache;
+import com.mxdl.customview.bitmap.ImageResizer;
+import com.mxdl.customview.bitmap.test.entity.Person;
+
+import java.io.BufferedInputStream;
+import java.io.BufferedOutputStream;
+import java.io.File;
+import java.io.FileDescriptor;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Description: <Test><br>
+ * Author:      mxdl<br>
+ * Date:        2019/11/28<br>
+ * Version:     V1.0.0<br>
+ * Update:     <br>
+ */
+public class Test {
+
+    private DiskLruCache mDiskLruCache;
+
+    public static void main(String[] args) {
+        //test();
+        //test2();
+    }
+
+    private void test2() {
+        File forder = Environment.getDownloadCacheDirectory();
+        try {
+            mDiskLruCache = DiskLruCache.open(forder, 100, 1, 50 * 1024 * 1024);
+            DiskLruCache.Editor editor = mDiskLruCache.edit("mxdl");
+            if (editor != null) {
+                OutputStream outputStream = editor.newOutputStream(0);
+                if (downloadUrlToStream("mxdl", outputStream)) {
+                    editor.commit();
+                } else {
+                    editor.abort();
+                }
+                mDiskLruCache.flush();
+            }
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+    public void getFile(String url){
+        Bitmap bitmap = null;
+        String key = hashKeyFormUrl(url);
+        DiskLruCache.Snapshot snapShot = null;
+        try {
+            snapShot = mDiskLruCache.get(key);
+            if (snapShot != null) {
+                FileInputStream fileInputStream = (FileInputStream)snapShot.getInputStream(0);
+                FileDescriptor fileDescriptor = fileInputStream.getFD();
+                bitmap = new ImageResizer().decodeSampledBitmapFromFileDescriptor(fileDescriptor,100,100);
+                if (bitmap != null) {
+                    //addBitmapToMemoryCache(key,bitmap);
+                }
+            }
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+
+    }
+    private String hashKeyFormUrl(String url) {
+        String cacheKey;
+        try {
+            final MessageDigest mDigest = MessageDigest.getInstance("MD5");
+            mDigest.update(url.getBytes());
+            cacheKey = bytesToHexString(mDigest.digest());
+        } catch (NoSuchAlgorithmException e) {
+            cacheKey = String.valueOf(url.hashCode());
+        }
+        return cacheKey;
+    }
+
+    private String bytesToHexString(byte[] bytes) {
+        StringBuilder sb = new StringBuilder();
+        for (int i = 0; i < bytes.length; i++) {
+            String hex = Integer.toHexString(0xFF & bytes[i]);
+            if (hex.length() == 1) {
+                sb.append('0');
+            }
+            sb.append(hex);
+        }
+        return sb.toString();
+    }
+
+    public boolean downloadUrlToStream(String urlString, OutputStream outputStream) {
+        HttpURLConnection urlConnection = null;
+        BufferedOutputStream out = null;
+        BufferedInputStream in = null;
+        try {
+            final URL url = new URL(urlString);
+            urlConnection = (HttpURLConnection) url.openConnection();
+            in = new BufferedInputStream(urlConnection.getInputStream(), 1024 * 1);
+            out = new BufferedOutputStream(outputStream, 1024 * 1);
+            int b;
+            while ((b = in.read()) != -1) {
+                out.write(b);
+            }
+            return true;
+        } catch (IOException e) {
+            Log.e("MYTAG", "downloadBitmap failed." + e);
+        } finally {
+            if (urlConnection != null) {
+                urlConnection.disconnect();
+            }
+            //MyUtils.close(out);
+            //MyUtils.close(in);
+        }
+        return false;
+    }
+
+    private static void test() {
+        HashMap<String, String> map1 = new HashMap<>();
+        map1.put("zhangsan", "zhangsan");
+        map1.put("lisi", "lisi");
+        map1.put("wangwu", "wangwu");
+        Set<Map.Entry<String, String>> entrySet1 = map1.entrySet();
+        Iterator<Map.Entry<String, String>> iterator1 = entrySet1.iterator();
+        while (iterator1.hasNext()) {
+            System.out.println(iterator1.next().toString());
+        }
+        System.out.println("==========================================");
+        LinkedHashMap<String, String> map = new LinkedHashMap<>();
+        map.put("zhangsan", "zhangsan");
+        map.put("lisi", "lisi");
+        map.put("wangwu", "wangwu");
+
+        String wangwu = map.get("zhangsan");
+        String put = map.put("zhaoliu", "zhaoliu");
+
+        Set<Map.Entry<String, String>> entrySet = map.entrySet();
+        Iterator<Map.Entry<String, String>> iterator = entrySet.iterator();
+        while (iterator.hasNext()) {
+            System.out.println(iterator.next().toString());
+        }
+    }
+}

app/src/main/java/com/mxdl/customview/bitmap/test/TestCacheActivity.java

+package com.mxdl.customview.bitmap.test;
+
+import androidx.appcompat.app.AppCompatActivity;
+
+import android.os.Bundle;
+import android.util.Log;
+import android.util.LruCache;
+
+import com.mxdl.customview.R;
+import com.mxdl.customview.bitmap.test.entity.Person;
+
+import java.util.Iterator;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.Set;
+
+public class TestCacheActivity extends AppCompatActivity {
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_test_cache);
+        long maxMemory = Runtime.getRuntime().maxMemory();
+        Log.v("MYTAG","maxMemary:"+maxMemory+"b");
+        Log.v("MYTAG","maxMemary:"+maxMemory/(1024)+"kb");
+        Log.v("MYTAG","maxMemary:"+maxMemory/(1024*1024)+"mb");
+
+        LruCache<String, Person> cache = new LruCache<>(3);
+        cache.put("0",new Person("0,",19));
+        cache.put("1",new Person("1,",19));
+        cache.put("2",new Person("2,",19));
+
+        Person person = cache.get("0");
+        //cache.put("3",new Person("3,",19));
+
+        LinkedHashMap<String, Person> linkedHashMap = (LinkedHashMap<String, Person>) cache.snapshot();
+        Set<String> set = linkedHashMap.keySet();
+        Iterator<String> iterator = set.iterator();
+        while(iterator.hasNext()){
+            Log.v("MYTAG",linkedHashMap.get(iterator.next()).toString());
+        }
+        Log.v("MYTAG","===============================-------------------------");
+
+        LruCache<String,String> map = new LruCache<>(3);
+        map.put("zhangsan","zhangsan");
+        map.put("lisi","lisi");
+        map.put("wangwu","wangwu");
+
+        String wangwu = map.get("zhangsan");
+        String put = map.put("zaholiu", "zhaoliou");
+        String put1 = map.put("zaholiu", "zhaoliou");
+        Log.v("MYTAG",put == null ? "null":"not null");
+        Log.v("MYTAG",put1 == null ? "null":"not null");
+
+        Set<Map.Entry<String, String>> entrySet = map.snapshot().entrySet();
+        Iterator<Map.Entry<String, String>> iterator1 = entrySet.iterator();
+        while(iterator1.hasNext()){
+            Log.v("MYTAG",iterator1.next().toString());
+        }
+    }
+
+}

app/src/main/java/com/mxdl/customview/bitmap/test/entity/Person.java

+package com.mxdl.customview.bitmap.test.entity;
+
+import androidx.annotation.NonNull;
+
+/**
+ * Description: <Person><br>
+ * Author:      mxdl<br>
+ * Date:        2019/11/28<br>
+ * Version:     V1.0.0<br>
+ * Update:     <br>
+ */
+public class Person {
+    public String name;
+    public int age;
+
+    public Person(String name, int age) {
+        this.name = name;
+        this.age = age;
+    }
+
+    @Override
+    public String toString() {
+        return "Person{" + "name='" + name + '\'' + ", age=" + age + '}';
+    }
+}

app/src/main/res/layout/activity_main.xml

@@ -62,5 +62,11 @@
             android:layout_height="wrap_content"
             android:text="TestAsyncTask"
             android:textAllCaps="false" />
+        <Button
+            android:id="@+id/btn_cache"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:text="Cache"
+            android:textAllCaps="false" />
     </LinearLayout>
 </androidx.core.widget.NestedScrollView>

app/src/main/res/layout/activity_test_cache.xml

+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".bitmap.test.TestCacheActivity">
+
+</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file