标签：android os io java ar cti sp 代码 log
对于复杂的对象存储android sdk本身没有提供相关api，如果想通过xml节点表示复杂对象在解析这块花的功夫就比较大了，于是找到一个简单方法，那就是用base64存储序列化的对象按string类型存储你懂的。/**
* SharedPreferences工具类
*
* @author bobby
*
*/
public class SharedPreferencesUtils {
Context context;
String name;
public SharedPreferencesUtils(Context context, String name) {
this.context = context;
this.name = name;
}
/**
* 根据key和预期的value类型获取value的值
*
* @param key
* @param clazz
* @return
*/
public <T> T getValue(String key, Class<T> clazz) {
if (context == null) {
throw new RuntimeException("请先调用带有context，name参数的构造！");
}
SharedPreferences sp = this.context.getSharedPreferences(this.name, Context.MODE_PRIVATE);
return getValue(key, clazz, sp);
}
/**
* 针对复杂类型存储<对象>
*
* @param key
* @param val
*/
public void setObject(String key, Object object) {
SharedPreferences sp = this.context.getSharedPreferences(this.name, Context.MODE_PRIVATE);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream out = null;
try {
out = new ObjectOutputStream(baos);
out.writeObject(object);
String objectVal = new String(Base64.encode(baos.toByteArray(), Base64.DEFAULT));
Editor editor = sp.edit();
editor.putString(key, objectVal);
editor.commit();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (baos != null) {
baos.close();
}
if (out != null) {
out.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
@SuppressWarnings("unchecked")
public <T> T getObject(String key, Class<T> clazz) {
SharedPreferences sp = this.context.getSharedPreferences(this.name, Context.MODE_PRIVATE);
if (sp.contains(key)) {
String objectVal = sp.getString(key, null);
byte[] buffer = Base64.decode(objectVal, Base64.DEFAULT);
ByteArrayInputStream bais = new ByteArrayInputStream(buffer);
ObjectInputStream ois = null;
try {
ois = new ObjectInputStream(bais);
T t = (T) ois.readObject();
return t;
} catch (StreamCorruptedException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} finally {
try {
if (bais != null) {
bais.close();
}
if (ois != null) {
ois.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
return null;
}
/**
* 对于外部不可见的过渡方法
*
* @param key
* @param clazz
* @param sp
* @return
*/
@SuppressWarnings("unchecked")
private <T> T getValue(String key, Class<T> clazz, SharedPreferences sp) {
T t;
try {
t = clazz.newInstance();
if (t instanceof Integer) {
return (T) Integer.valueOf(sp.getInt(key, 0));
} else if (t instanceof String) {
return (T) sp.getString(key, "");
} else if (t instanceof Boolean) {
return (T) Boolean.valueOf(sp.getBoolean(key, false));
} else if (t instanceof Long) {
return (T) Long.valueOf(sp.getLong(key, 0L));
} else if (t instanceof Float) {
return (T) Float.valueOf(sp.getFloat(key, 0L));
}
} catch (InstantiationException e) {
e.printStackTrace();
Log.e("system", "类型输入错误或者复杂类型无法解析[" + e.getMessage() + "]");
} catch (IllegalAccessException e) {
e.printStackTrace();
Log.e("system", "类型输入错误或者复杂类型无法解析[" + e.getMessage() + "]");
}
Log.e("system", "无法找到" + key + "对应的值");
return null;
}
}
标签：android os io java ar cti sp 代码 log
原文地址：http://my.oschina.net/ibobby/blog/311446
