code: public boolean isValueExistForKey(String key) {
  		boolean isValueExists;
  		try {
  			String string = getString(key, "");
  			isValueExists = !string.equalsIgnoreCase("");
  		} catch (ClassCastException e) {
  			try {
  				int anInt = getInt(key, 0);
  				isValueExists = anInt != 0;
  			} catch (ClassCastException e1) {
  				try {
  					long aLong = getLong(key, 0);
  					isValueExists = aLong != 0;
  				} catch (ClassCastException e2) {
  					try {
  						float aFloat = getFloat(key, 0f);
  						isValueExists = aFloat != 0;
  					} catch (ClassCastException e3) {
  						try {
  							boolean aBoolean = getBoolean(key, false);
  							isValueExists = !aBoolean;
  						} catch (Exception e4) {
  							isValueExists = false;
  							e.printStackTrace();
  						}
  					}
  
  				}
  
  			}
  		} catch (Exception e) {
  			isValueExists = false;
  		}
  		return isValueExists;
  	}
docs: Check if value exists for key.
  
  @param key
  : Key for which we need to check the value exists or not.
  
  @return : <code>true</code> if the value exists and it's other than default data.