android 超轻量级数据存储类，android数据存储, import j

android 超轻量级数据存储类，android数据存储, import j

    import java.io.File;      import java.io.FileInputStream;      import java.io.FileNotFoundException;      import java.io.FileOutputStream;      import java.io.IOException;      import java.io.OutputStream;      import java.io.UnsupportedEncodingException;      import java.net.URLDecoder;      import java.net.URLEncoder;      import java.util.HashMap;      import java.util.Map;      import java.util.Properties;      import java.util.Set;      import android.content.Context;      /**      * android本地存储 ，主要用于存储简单key value键值对。提供增、删、改、查方法。 可自定义路径      *       * @author Administrator      *      */      public class LocalStorage {          private static Properties properties = new Properties();          private static String filepath;          private LocalStorage() {          }          /**          *           * @param ctx          * @param fileName          *            文件名          * @return          */          public static LocalStorage get(Context ctx, String fileName) {              return get(ctx.getCacheDir() + "/" + fileName);          }          /**          *           * @param filePath          *            文件绝对路径          * @return          */          public static LocalStorage get(String filePath) {              createFile(filePath);              filepath = filePath;              try {                  properties.load(new FileInputStream(filepath));                  return new LocalStorage();              } catch (FileNotFoundException e) {                  e.printStackTrace();              } catch (IOException e) {                  e.printStackTrace();              }              return null;          }          private static void createFile(String fileName) {              File file = new File(fileName);              if (!file.exists()) {                  String path = file.getAbsolutePath();                  String[] sourceStrArray = path.split("/");                  String dirPath = "";                  for (int i = 0; i < sourceStrArray.length - 1; i++) {                      if (!sourceStrArray[i].equals("")) {                          dirPath += "/" + sourceStrArray[i];                      }                  }                  new File(dirPath).mkdirs();                  try {                      file.createNewFile();                  } catch (IOException e) {                      e.printStackTrace();                  }              }          }          public String getAsString(String key) {              if (key == null) {                  return null;              }              Properties props = new Properties();              try {                  props.load(new FileInputStream(filepath));                  String value = props.getProperty(key);                  value = URLDecoder.decode(value, "utf-8");                  return value;              } catch (Exception e) {                  e.printStackTrace();                  return null;              }          }          public int getAsInt(String key) {              String str = getAsString(key);              if (str == null)                  return -9999;              return Integer.valueOf(str).intValue();          }          public boolean getAsBoolean(String key) {              String str = getAsString(key);              if (str == null)                  return false;              if (str.equals("true"))                  return true;              return false;          }          public long getAsLong(String key) {              String str = getAsString(key);              if (str == null)                  return -9999;              return Long.valueOf(str).longValue();          }          public float getAsFloat(String key) {              String str = getAsString(key);              if (str == null)                  return -9999;              return Float.valueOf(str).floatValue();          }          public double getAsDouble(String key) {              String str = getAsString(key);              if (str == null)                  return -9999;              return Double.valueOf(str).doubleValue();          }          /**          * 添加          *           * @param keyname          * @param keyvalue          */          public void put(String keyname, Object keyvalue) {              // 处理中文乱码              String value = keyvalue.toString();              try {                  value = URLEncoder.encode(value, "utf-8");              } catch (UnsupportedEncodingException e1) {                  e1.printStackTrace();              }              try {                  OutputStream fos = new FileOutputStream(filepath);                  properties.setProperty(keyname, value);                  properties.store(fos, null);              } catch (IOException e) {              }          }          /**          * 更新          *           * @param keyname          * @param keyvalue          */          public void update(String keyname, String keyvalue) {              try {                  properties.load(new FileInputStream(filepath));                  OutputStream fos = new FileOutputStream(filepath);                  properties.setProperty(keyname, keyvalue);                  properties.store(fos, null);              } catch (IOException e) {              }          }          /**          * 根据key删除          *           * @param key          */          public void delete(String key) {              try {                  FileInputStream fis = new FileInputStream(filepath);                  properties.load(fis);                  Map<String, String> map = new HashMap<String, String>();                  Set<Object> keySet = properties.keySet();                  for (Object object : keySet) {                      String objectkey = (String) object;                      String value = (String) properties.get(objectkey);                      map.put(objectkey, value);                  }                  map.remove(key);                  properties.remove(key);                  for (java.util.Map.Entry<String, String> entry : map.entrySet()) {                      properties.setProperty(entry.getKey(), entry.getValue());                  }                  FileOutputStream fos = new FileOutputStream(filepath);                  properties.store(fos, "delete key:" + key);                  fos.close();                  fis.close();              } catch (Exception e) {                  e.printStackTrace();              }          }      }  

使用方法

    // 这里获取LocalStorage对象。参数也可以为文件绝对路径，当然也可以直接传入Context和文件名。          LocalStorage localStorage = LocalStorage.get("test.txt");          // 增加          localStorage.put("key", "哈哈");          // 更新          localStorage.update("key", "value");          // 查找，这里提供多个getAs 方法。取数据找到相应的数据类型          localStorage.getAsString("key");          // 删除          localStorage.delete("key");