实现对网络数据的缓存

Author: alafighting

app/src/main/AndroidManifest.xml

@@ -1,6 +1,8 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
           package="com.im4j.kakacache.rxjava.demo">
 
+    <uses-permission android:name="android.permission.INTERNET" />
+
     <application
         android:allowBackup="true"
         android:icon="@mipmap/ic_launcher"

app/src/main/java/com/im4j/kakacache/rxjava/demo/MainActivity.java

@@ -3,21 +3,41 @@
 import android.os.Bundle;
 import android.support.annotation.Nullable;
 import android.support.v7.app.AppCompatActivity;
+import android.util.Log;
+import android.widget.Button;
+
+import com.im4j.kakacache.rxjava.netcache.RxRemoteCache;
+
+import java.util.concurrent.TimeUnit;
 
 /**
  * Demo主界面
  * @version alafighting 2016-06
  */
 public class MainActivity extends AppCompatActivity {
+    static final String KEY_CACHE = "key_cache";
+
+    private Button btnTest;
 
     @Override
     protected void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
+        setContentView(R.layout.actiity_main);
 
-//        CacheCore.Builder builder = new CacheCore.Builder();
-//        CacheCore manager = builder.create();
-//
-//        manager.save("test1", "value123");
-//        manager.save("boolean1", true);
+        btnTest = (Button) findViewById(R.id.btn_test_cache);
+        btnTest.setOnClickListener(view -> {
+            RxRemoteCache.cache(remote(), KEY_CACHE).subscribe(data -> {
+                Log.e("main", "next  data="+data);
+            }, error -> {
+                Log.e("main", "error", error);
+            }, () -> {
+                Log.e("main", "completed");
+            });
+        });
     }
+
+    private rx.Observable<String> remote() {
+        return rx.Observable.just("test remote").delay(3, TimeUnit.SECONDS);
+    }
+
 }

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

@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="utf-8"?>
+<RelativeLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+
+    <Button
+        android:id="@+id/btn_test_cache"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_centerHorizontal="true"
+        android:text="测试缓存"/>
+
+</RelativeLayout>

library/src/main/AndroidManifest.xml

@@ -1,6 +1,9 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
           package="com.im4j.kakacache.rxjava">
 
+    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
+    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
+
     <application
         android:allowBackup="true"
         android:label="@string/app_name"

library/src/main/java/com/im4j/kakacache/rxjava/common/utils/Utils.java

@@ -24,6 +24,15 @@ public static <T> T checkNotNull(T obj) {
         }
         return obj;
     }
+    /**
+     * 不为空
+     */
+    public static <T> T checkNotNull(T obj, String message) {
+        if (obj == null) {
+            throw new NullException(message);
+        }
+        return obj;
+    }
 
     /**
      * 不小于0

library/src/main/java/com/im4j/kakacache/rxjava/manager/CacheManager.java

@@ -70,22 +70,4 @@ void _clear() throws CacheException {
         }
     }
 
-
-
-    /**
-     * 构造器
-     */
-    public static abstract class Builder {
-        CacheCore cache;
-
-        public Builder(CacheCore cache) {
-            this.cache = cache;
-        }
-
-        public RxJavaCacheManager.Builder rxjava() {
-            return new RxJavaCacheManager.Builder(cache);
-        }
-
-    }
-
 }

…e/rxjava/manager/RxJavaCacheManager.java …cache/rxjava/manager/RxCacheManager.javalibrary/src/main/java/com/im4j/kakacache/rxjava/manager/RxJavaCacheManager.java renamed to library/src/main/java/com/im4j/kakacache/rxjava/manager/RxCacheManager.java library/src/main/java/com/im4j/kakacache/rxjava/manager/RxJavaCacheManager.java renamed to library/src/main/java/com/im4j/kakacache/rxjava/manager/RxCacheManager.java

@@ -1,7 +1,6 @@
 package com.im4j.kakacache.rxjava.manager;
 
 import com.im4j.kakacache.rxjava.common.exception.CacheException;
-import com.im4j.kakacache.rxjava.common.exception.NotFoundException;
 import com.im4j.kakacache.rxjava.core.CacheCore;
 import com.im4j.kakacache.rxjava.core.CacheTarget;
 
@@ -12,7 +11,7 @@
  * RxJava模式缓存管理
  * @version alafighting 2016-04
  */
-public class RxJavaCacheManager extends CacheManager {
+public class RxCacheManager extends CacheManager {
 
     private static abstract class SimpleSubscribe<T> implements rx.Observable.OnSubscribe<T> {
         @Override
@@ -30,7 +29,7 @@ public final void call(Subscriber<? super T> subscriber) {
     }
 
 
-    public RxJavaCacheManager(CacheCore cache) {
+    public RxCacheManager(CacheCore cache) {
         super(cache);
     }
 
@@ -43,9 +42,9 @@ public <T> rx.Observable<T> load(final String key) {
             @Override
             void execute(Subscriber<? super T> subscriber) {
                 T value = _load(key);
-                if (value == null) {
-                    subscriber.onError(new NotFoundException("找不到缓存’"+key+"'"));
-                }
+//                if (value == null) {
+//                    subscriber.onError(new NotFoundException("找不到缓存’"+key+"'"));
+//                }
                 subscriber.onNext(value);
             }
         }).subscribeOn(Schedulers.computation());
@@ -107,19 +106,4 @@ void execute(Subscriber<? super Boolean> subscriber) {
         });
     }
 
-
-
-    /**
-     * 构造器
-     */
-    public static class Builder extends CacheManager.Builder {
-        public Builder(CacheCore cache) {
-            super(cache);
-        }
-
-        public RxJavaCacheManager create() {
-            return new RxJavaCacheManager(cache);
-        }
-    }
-
 }

library/src/main/java/com/im4j/kakacache/rxjava/netcache/CacheTransformer.java

@@ -0,0 +1,56 @@
+package com.im4j.kakacache.rxjava.netcache;
+
+import android.util.Log;
+
+import rx.Observable;
+import rx.schedulers.Schedulers;
+
+/**
+ * 将Observable转换为自动处理缓存的源
+ * @version alafighting 2016-06
+ */
+public class CacheTransformer<T> implements Observable.Transformer<T, CacheTransformer.CacheData<T>> {
+
+    private String key;
+    public CacheTransformer(String key) {
+        this.key = key;
+    }
+
+    @Override
+    public Observable<CacheData<T>> call(Observable<T> source) {
+        return Observable.concat(
+                RxRemoteCache.load(key).map(it -> new CacheData<T>(From.Cache, key, (T)it)),
+                source.map(it -> {
+                    RxRemoteCache.save(key, it).subscribe(status -> Log.e("save status", "status="+status) );
+                    Log.e("transformer", "save  key="+key+", value="+it);
+                    return new CacheData<T>(From.Remote, key, it);
+                })
+        ).first(it -> it.data != null).subscribeOn(Schedulers.io());
+    }
+
+    public static final class CacheData<T> {
+        public From from;
+        public String key;
+        public T data;
+
+        public CacheData(From from, String key, T data) {
+            this.from = from;
+            this.key = key;
+            this.data = data;
+        }
+
+        @Override
+        public String toString() {
+            return "CacheData{" +
+                    "from=" + from +
+                    ", key='" + key + '\'' +
+                    ", data=" + data +
+                    '}';
+        }
+    }
+
+    public static enum From {
+        Remote, Cache
+    }
+
+}

library/src/main/java/com/im4j/kakacache/rxjava/netcache/RxRemoteCache.java

@@ -0,0 +1,71 @@
+package com.im4j.kakacache.rxjava.netcache;
+
+
+import android.os.Environment;
+import android.util.Log;
+
+import com.im4j.kakacache.rxjava.core.CacheCore;
+import com.im4j.kakacache.rxjava.core.CacheTarget;
+import com.im4j.kakacache.rxjava.core.disk.converter.SerializableDiskConverter;
+import com.im4j.kakacache.rxjava.core.disk.journal.LRUDiskJournal;
+import com.im4j.kakacache.rxjava.core.disk.storage.FileDiskStorage;
+import com.im4j.kakacache.rxjava.core.memory.journal.LRUMemoryJournal;
+import com.im4j.kakacache.rxjava.core.memory.storage.SimpleMemoryStorage;
+import com.im4j.kakacache.rxjava.manager.RxCacheManager;
+
+import java.io.File;
+
+import rx.Observable;
+
+/**
+ * RxJava的远程数据缓存处理
+ * @version alafighting 2016-06
+ */
+public class RxRemoteCache {
+
+    private RxRemoteCache() {
+    }
+
+    private static RxCacheManager cacheManager;
+    private static int expires = 12 * 60 * 60 * 1000;
+
+    private static RxCacheManager getCacheManager() {
+        if (cacheManager == null) {
+            File storageDir = new File(Environment.getExternalStorageDirectory(), "aaa_test");
+            Log.e("RxRemoteCache", "storageDir="+storageDir.getAbsolutePath());
+
+            storageDir.mkdirs();
+
+            CacheCore.Builder coreBuilder = new CacheCore.Builder();
+            coreBuilder.memory(new SimpleMemoryStorage());
+            coreBuilder.memoryJournal(new LRUMemoryJournal());
+            coreBuilder.memoryMax(10 * 1024 * 1024, 1000);
+            coreBuilder.disk(new FileDiskStorage(storageDir));
+            coreBuilder.diskJournal(new LRUDiskJournal());
+            coreBuilder.diskMax(30 * 1024 * 1024, 10 * 1000);
+            coreBuilder.diskConverter(new SerializableDiskConverter());
+            CacheCore core = coreBuilder.create();
+            cacheManager = new RxCacheManager(core);
+        }
+        return cacheManager;
+    }
+
+    public static <T> rx.Observable<T> load(String key) {
+        return getCacheManager().load(key);
+    }
+
+    public static <T> rx.Observable<Boolean> save(String key, T value, CacheTarget target) {
+        return getCacheManager().save(key, value, expires, target);
+    }
+
+    public static <T> rx.Observable<Boolean> save(String key, T value) {
+        return save(key, value, CacheTarget.MemoryDisk);
+    }
+
+
+
+    public static <T> Observable<CacheTransformer.CacheData<T>> cache(Observable<T> observable, String key) {
+        return observable.compose(new CacheTransformer<>(key));
+    }
+
+}