Gist for Preferences.java, Utility class for handling read/write operations using SharedPreferences

Preferences.java

/*
 * Copyright (c) 2017, marlonlom
 *
 * Licensed under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on
 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import android.content.Context;
import android.content.SharedPreferences;

/**
 * Utility class for handling read/write operations using {@link android.content.SharedPreferences}
 *
 * @author marlonlom
 */
public final class Preferences {

    /**
     * Empty string constant for default string preference values.
     */
    private static final String EMPTY_STRING = "";
    /**
     * Empty string constant for default float preference values.
     */
    private static final float FLOAT_DEFAULT = -1;

    /**
     * With app preferences builder.
     *
     * @param context     application context
     * @param packageName application package name
     * @return the app preferences builder
     */
    public static Preferences.Builder with(Context context, String packageName) {
        return new Preferences.Builder(context, packageName);
    }

    /**
     * Builder inner class for Application preferences manager.
     *
     * @author marlonlom
     */
    public static class Builder {

        /**
         * Shared preferences manager for general use.
         */
        private SharedPreferences preferences;

        /**
         * Default constructor for builder
         *
         * @param context     application context
         * @param packageName application package name
         */
        public Builder(Context context, String packageName) {
            this.preferences =
                    context.getSharedPreferences(packageName.concat(".prefs"), Context.MODE_PRIVATE);
        }

        /**
         * Reads and return an int value for preference
         *
         * @param key preference key
         * @return preference int value
         */
        public int readInt(String key) {
            return this.preferences.getInt(key, -1);
        }

        /**
         * Put an int value for preference
         *
         * @param key   preference key
         * @param value preference value
         */
        public void saveInt(String key, int value) {
            final SharedPreferences.Editor editor = this.preferences.edit();
            editor.putInt(key, value);
            editor.apply();
        }

        /**
         * Put a float value for preference
         *
         * @param key   preference key
         * @param value preference value
         */
        public void saveFloat(String key, float value) {
            final SharedPreferences.Editor editor = this.preferences.edit();
            editor.putFloat(key, value);
            editor.apply();
        }

        /**
         * Reads and return an float value for preference
         *
         * @param key preference key
         * @return preference float value
         */
        public float readFloat(String key) {
            return this.preferences.getFloat(key, FLOAT_DEFAULT);
        }

        /**
         * Put a string value for preference
         *
         * @param key   preference key
         * @param value preference value
         */
        public void saveString(String key, String value) {
            final SharedPreferences.Editor editor = this.preferences.edit();
            editor.putString(key, value);
            editor.apply();
        }

        /**
         * Reads and return an string value for preference
         *
         * @param key preference key
         * @return preference string value
         */
        public String readString(String key) {
            return this.preferences.getString(key, EMPTY_STRING);
        }

        /**
         * Put a boolean value for preference.
         *
         * @param key   preference key
         * @param value preference value
         */
        public void saveBoolean(String key, Boolean value) {
            final SharedPreferences.Editor editor = this.preferences.edit();
            editor.putBoolean(key, value);
            editor.apply();
        }

        /**
         * Reads and return an boolean value for preference
         *
         * @param key          preference key
         * @param defaultValue boolean default value
         * @return preference string value
         */
        public Boolean readBoolean(String key, Boolean defaultValue) {
            return this.preferences.getBoolean(key, defaultValue);
        }
    }
}