Class Preferences


  • public final class Preferences
    extends Object
    The preferences class provides a relatively simple way to save important values to the roboRIO to access the next time the roboRIO is booted.

    This class loads and saves from a file inside the roboRIO. The user can not access the file directly, but may modify values at specific fields which will then be automatically saved to the file by the NetworkTables server.

    This class is thread safe.

    This will also interact with NetworkTable by creating a table called "Preferences" with all the key-value pairs.

    • Method Detail

      • getInstance

        public static Preferences getInstance()
        Returns the preferences instance.
        Returns:
        the preferences instance
      • getKeys

        public Vector<String> getKeys()
        Gets the vector of keys.
        Returns:
        a vector of the keys
      • putString

        public void putString​(String key,
                              String value)
        Puts the given string into the preferences table.
        Parameters:
        key - the key
        value - the value
        Throws:
        NullPointerException - if value is null
      • putInt

        public void putInt​(String key,
                           int value)
        Puts the given int into the preferences table.
        Parameters:
        key - the key
        value - the value
      • putDouble

        public void putDouble​(String key,
                              double value)
        Puts the given double into the preferences table.
        Parameters:
        key - the key
        value - the value
      • putFloat

        public void putFloat​(String key,
                             float value)
        Puts the given float into the preferences table.
        Parameters:
        key - the key
        value - the value
      • putBoolean

        public void putBoolean​(String key,
                               boolean value)
        Puts the given boolean into the preferences table.
        Parameters:
        key - the key
        value - the value
      • putLong

        public void putLong​(String key,
                            long value)
        Puts the given long into the preferences table.
        Parameters:
        key - the key
        value - the value
      • containsKey

        public boolean containsKey​(String key)
        Returns whether or not there is a key with the given name.
        Parameters:
        key - the key
        Returns:
        if there is a value at the given key
      • remove

        public void remove​(String key)
        Remove a preference.
        Parameters:
        key - the key
      • removeAll

        public void removeAll()
        Remove all preferences.
      • getString

        public String getString​(String key,
                                String backup)
        Returns the string at the given key. If this table does not have a value for that position, then the given backup value will be returned.
        Parameters:
        key - the key
        backup - the value to return if none exists in the table
        Returns:
        either the value in the table, or the backup
      • getInt

        public int getInt​(String key,
                          int backup)
        Returns the int at the given key. If this table does not have a value for that position, then the given backup value will be returned.
        Parameters:
        key - the key
        backup - the value to return if none exists in the table
        Returns:
        either the value in the table, or the backup
      • getDouble

        public double getDouble​(String key,
                                double backup)
        Returns the double at the given key. If this table does not have a value for that position, then the given backup value will be returned.
        Parameters:
        key - the key
        backup - the value to return if none exists in the table
        Returns:
        either the value in the table, or the backup
      • getBoolean

        public boolean getBoolean​(String key,
                                  boolean backup)
        Returns the boolean at the given key. If this table does not have a value for that position, then the given backup value will be returned.
        Parameters:
        key - the key
        backup - the value to return if none exists in the table
        Returns:
        either the value in the table, or the backup
      • getFloat

        public float getFloat​(String key,
                              float backup)
        Returns the float at the given key. If this table does not have a value for that position, then the given backup value will be returned.
        Parameters:
        key - the key
        backup - the value to return if none exists in the table
        Returns:
        either the value in the table, or the backup
      • getLong

        public long getLong​(String key,
                            long backup)
        Returns the long at the given key. If this table does not have a value for that position, then the given backup value will be returned.
        Parameters:
        key - the key
        backup - the value to return if none exists in the table
        Returns:
        either the value in the table, or the backup