android SharePreference缓存存储List＜Bean＞

ゝ一纸荒年。 2021-09-08 00:20 353阅读 0赞

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NzZG5fbG92ZVFpbmdRaW5n_size_16_color_FFFFFF_t_70][]

使用环境:

项目中使用到缓存文件，但是不满足常规存储，需要用到存储List<bean>

使用方法：

1 讲list<Bean> 通过Gson转换为Json字符串，存储在sp缓存中

SpUtils.put(Utils.getContext(),"module_key",new Gson().toJson(listSpBeans));

2 将json字符串取出，通过解析为指定类型进行解析还原List<Bean>

String res = (String) SpUtils.get(Utils.getContext(), "module_key", "");
            if (!TextUtils.isEmpty(res)) {
                listType = new TypeToken<List<SearchSongBean.ResultBean>>() {
                }.getType();
                gson = new Gson();
                List<Bean> listSpBeans = gson.fromJson(res, listType);
            }

3 下面关于SpUtils的代码，懒得封装的朋友可以直接复制走

import android.content.Context;
    import android.content.SharedPreferences;
    import android.util.Base64;
    
    import com.goldze.mvvmhabit.app.AppApplication;
    
    import java.io.ByteArrayInputStream;
    import java.io.ByteArrayOutputStream;
    import java.io.IOException;
    import java.io.ObjectInputStream;
    import java.io.ObjectOutputStream;
    import java.io.Serializable;
    import java.lang.reflect.InvocationTargetException;
    import java.lang.reflect.Method;
    import java.util.ArrayList;
    import java.util.List;
    import java.util.Map;
    
    /**
     * Created by SensYang on 2019/02/27 10:32
     */
    
    public class SpUtils {
    
    
        public SpUtils() {
            /* cannot be instantiated */
            throw new UnsupportedOperationException("cannot be instantiated");
        }
    
        public static final String FILE_NAME = "ma_object";
    
        public static String put(String key, Object object){
            SharedPreferences sp = AppApplication.getInstance().getApplicationContext().getSharedPreferences(FILE_NAME, Context.MODE_PRIVATE);
            SharedPreferences.Editor editor = sp.edit();
    
            if (object instanceof String) {
                editor.putString(key, (String) object);
            } else if (object instanceof Integer) {
                editor.putInt(key, (Integer) object);
            } else if (object instanceof Boolean) {
                editor.putBoolean(key, (Boolean) object);
            } else if (object instanceof Float) {
                editor.putFloat(key, (Float) object);
            } else if (object instanceof Long) {
                editor.putLong(key, (Long) object);
            } else {
                editor.putString(key, object.toString());
            }
    
            SpUtils.SharedPreferencesCompat.apply(editor);
            return key;
        }
    
    
        public static String put(Context context, String key, Object object) {
    
            SharedPreferences sp = context.getSharedPreferences(FILE_NAME, Context.MODE_PRIVATE);
            SharedPreferences.Editor editor = sp.edit();
    
            if (object instanceof String) {
                editor.putString(key, (String) object);
            } else if (object instanceof Integer) {
                editor.putInt(key, (Integer) object);
            } else if (object instanceof Boolean) {
                editor.putBoolean(key, (Boolean) object);
            } else if (object instanceof Float) {
                editor.putFloat(key, (Float) object);
            } else if (object instanceof Long) {
                editor.putLong(key, (Long) object);
            } else {
                editor.putString(key, object.toString());
            }
    
            SpUtils.SharedPreferencesCompat.apply(editor);
            return key;
        }
    
        public static Object get(String key, Object defaultObject){
            SharedPreferences sp = AppApplication.getInstance().getApplicationContext().getSharedPreferences(FILE_NAME, Context.MODE_PRIVATE);
    
            if (defaultObject instanceof String) {
                return sp.getString(key, (String) defaultObject);
            } else if (defaultObject instanceof Integer) {
                return sp.getInt(key, (Integer) defaultObject);
            } else if (defaultObject instanceof Boolean) {
                return sp.getBoolean(key, (Boolean) defaultObject);
            } else if (defaultObject instanceof Float) {
                return sp.getFloat(key, (Float) defaultObject);
            } else if (defaultObject instanceof Long) {
                return sp.getLong(key, (Long) defaultObject);
            }
    
            return null;
        }
    
        public static Object get(Context context, String key, Object defaultObject) {
            SharedPreferences sp = context.getSharedPreferences(FILE_NAME, Context.MODE_PRIVATE);
    
            if (defaultObject instanceof String) {
                return sp.getString(key, (String) defaultObject);
            } else if (defaultObject instanceof Integer) {
                return sp.getInt(key, (Integer) defaultObject);
            } else if (defaultObject instanceof Boolean) {
                return sp.getBoolean(key, (Boolean) defaultObject);
            } else if (defaultObject instanceof Float) {
                return sp.getFloat(key, (Float) defaultObject);
            } else if (defaultObject instanceof Long) {
                return sp.getLong(key, (Long) defaultObject);
            }
    
            return null;
        }
    
        public static void remove(Context context, String key) {
            SharedPreferences sp = context.getSharedPreferences(FILE_NAME, Context.MODE_PRIVATE);
            SharedPreferences.Editor editor = sp.edit();
            editor.remove(key);
            SpUtils.SharedPreferencesCompat.apply(editor);
        }
    
        public static void clear(Context context) {
            SharedPreferences sp = context.getSharedPreferences(FILE_NAME, Context.MODE_PRIVATE);
            SharedPreferences.Editor editor = sp.edit();
            editor.clear();
            SpUtils.SharedPreferencesCompat.apply(editor);
        }
    
        public static boolean contains(Context context, String key) {
            SharedPreferences sp = context.getSharedPreferences(FILE_NAME, Context.MODE_PRIVATE);
            return sp.contains(key);
        }
    
        public static Map<String, ?> getAll(Context context) {
            SharedPreferences sp = context.getSharedPreferences(FILE_NAME, Context.MODE_PRIVATE);
            return sp.getAll();
        }
    
        private static class SharedPreferencesCompat {
            private static final Method sApplyMethod = findApplyMethod();
            @SuppressWarnings({"unchecked", "rawtypes"})
            private static Method findApplyMethod() {
                try {
                    Class clz = SharedPreferences.Editor.class;
                    return clz.getMethod("apply");
                } catch (NoSuchMethodException e) {
                }
    
                return null;
            }
    
            public static void apply(SharedPreferences.Editor editor) {
                try {
                    if (sApplyMethod != null) {
                        sApplyMethod.invoke(editor);
                        return;
                    }
                } catch (IllegalArgumentException e) {
                } catch (IllegalAccessException e) {
                } catch (InvocationTargetException e) {
                }
                editor.commit();
            }
        }
    
        public static void putBean(String key , Object obj){
            putBean(AppApplication.getInstance().getApplicationContext(),key,obj);
        }
    
        public static void putBean(Context context, String key, Object obj) {
            if (obj instanceof Serializable) {
                try {
                    ByteArrayOutputStream baos = new ByteArrayOutputStream();
                    ObjectOutputStream oos = new ObjectOutputStream(baos);
                    oos.writeObject(obj);
                    String string64 = new String(Base64.encode(baos.toByteArray(),
                            0));
                    SharedPreferences sp = context.getSharedPreferences(FILE_NAME, Context.MODE_PRIVATE);
                    SharedPreferences.Editor editor = sp.edit();
                    editor.putString(key, string64).commit();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            } else {
                throw new IllegalArgumentException(
                        "the obj must implement Serializble");
            }
        }
    
        public static Object getBean(String key){
            return getBean(AppApplication.getInstance().getApplicationContext(),key);
        }
    
        public static Object getBean(Context context, String key) {
            Object obj = null;
            SharedPreferences sp = context.getSharedPreferences(FILE_NAME, Context.MODE_PRIVATE);
            try {
                String base64 = sp.getString(key, "");
                if (base64.equals("")) {
                    return null;
                }
                byte[] base64Bytes = Base64.decode(base64.getBytes(), 1);
                ByteArrayInputStream bais = new ByteArrayInputStream(base64Bytes);
                ObjectInputStream ois = new ObjectInputStream(bais);
                obj = ois.readObject();
            } catch (Exception e) {
                e.printStackTrace();
            }
            return obj;
        }
    
        /**
         * 存储List<String>
         *
         * @param context
         * @param key
         *            List<String>对应的key
         * @param strList
         *            对应需要存储的List<String>
         */
        public static void putStrListValue(Context context, String key,
                                           List<String> strList) {
            if (null == strList) {
                return;
            }
            // 保存之前先清理已经存在的数据，保证数据的唯一性
            removeStrList(context, key);
            int size = strList.size();
            putIntValue(context, key + "size", size);
            for (int i = 0; i < size; i++) {
                putStringValue(context, key + i, strList.get(i));
            }
        }
    
        /**
         * 存储数据(String)
         *
         * @param context
         * @param key
         * @param value
         */
        private static void putStringValue(Context context, String key, String value) {
            SharedPreferences.Editor sp = context.getSharedPreferences(SETTING, Context.MODE_PRIVATE)
                    .edit();
            sp.putString(key, value);
            sp.commit();
        }
    
        /**
         * 取出数据（int)
         *
         * @param context
         * @param key
         * @param defValue
         *            默认值
         * @return
         */
        private static int getIntValue(Context context, String key, int defValue) {
            SharedPreferences sp = context.getSharedPreferences(SETTING,
                    Context.MODE_PRIVATE);
            int value = sp.getInt(key, defValue);
            return value;
        }
    
        /**
         * 取出数据（String)
         *
         * @param context
         * @param key
         * @param defValue
         *            默认值
         * @return
         */
        private static String getStringValue(Context context, String key,
                                             String defValue) {
            SharedPreferences sp = context.getSharedPreferences(SETTING,
                    Context.MODE_PRIVATE);
            String value = sp.getString(key, defValue);
            return value;
        }
    
        /**
         * 取出List<String>
         *
         * @param context
         * @param key
         *            List<String> 对应的key
         * @return List<String>
         */
        public static List<String> getStrListValue(Context context, String key) {
            List<String> strList = new ArrayList<String>();
            int size = getIntValue(context, key + "size", 0);
            //Log.d("sp", "" + size);
            for (int i = 0; i < size; i++) {
                strList.add(getStringValue(context, key + i, null));
            }
            return strList;
        }
    
        /**
         * 清空List<String>所有数据
         *
         * @param context
         * @param key
         *            List<String>对应的key
         */
        public static void removeStrList(Context context, String key) {
            int size = getIntValue(context, key + "size", 0);
            if (0 == size) {
                return;
            }
            remove(context, key + "size");
            for (int i = 0; i < size; i++) {
                remove(context, key + i);
            }
        }
    
        /**
         * @Description TODO 清空List<String>单条数据
         * @param context
         * @param key
         *            List<String>对应的key
         * @param str
         *            List<String>中的元素String
         */
        public static void removeStrListItem(Context context, String key, String str) {
            int size = getIntValue(context, key + "size", 0);
            if (0 == size) {
                return;
            }
            List<String> strList = getStrListValue(context, key);
            // 待删除的List<String>数据暂存
            List<String> removeList = new ArrayList<String>();
            for (int i = 0; i < size; i++) {
                if (str.equals(strList.get(i))) {
                    if (i >= 0 && i < size) {
                        removeList.add(strList.get(i));
                        remove(context, key + i);
                        putIntValue(context, key + "size", size - 1);
                    }
                }
            }
            strList.removeAll(removeList);
            // 删除元素重新建立索引写入数据
            putStrListValue(context, key, strList);
        }
    
        /**
         * 存储数据(Int)
         *
         * @param context
         * @param key
         * @param value
         */
        private static void putIntValue(Context context, String key, int value) {
            SharedPreferences.Editor sp = context.getSharedPreferences(SETTING, Context.MODE_PRIVATE)
                    .edit();
            sp.putInt(key, value);
            sp.commit();
        }
    
    
    
        /** 数据存储的XML名称 **/
        public final static String SETTING = "SharedPrefsStrList";
    }

更多讨论欢迎来聊： 88627109

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NzZG5fbG92ZVFpbmdRaW5n_size_16_color_FFFFFF_t_70]: /images/20210901/2c814ad14c2247a0b4667a33b2a1ef7d.png