/*
 * Copyright (C) 2017 The Android Open Source Project
 *
 * 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.
 */
package com.android.settings.battery;
 import android.content.Context;
import android.support.v7.preference.Preference;
 import com.android.settings.core.PreferenceControllerMixin;
import com.android.settingslib.core.AbstractPreferenceController;
 import java.io.BufferedReader;
import java.io.FileReader;
 public class BatteryTechPreferenceController extends AbstractPreferenceController implements
        PreferenceControllerMixin {
     private static final String KEY_BATTERY_TECH = "battery_tech";
    private static final String BATTERY_TECH_PATH = "sys/class/power_supply/battery/technology";
     public BatteryTechPreferenceController(Context context) {
        super(context);
    }
     @Override
    public boolean isAvailable() {
        return true;
    }
     @Override
    public void updateState(Preference preference) {
        super.updateState(preference);
        preference.setSummary(getBatteryTech());
    }
     private static String readOneLine(String fname) {
        BufferedReader br;
        String line = null;
        try {
            br = new BufferedReader(new FileReader(fname), 512);
            try {
                line = br.readLine();
            } finally {
                br.close();
            }
        } catch (Exception e) {
            return null;
        }
        return line;
    }
     String getBatteryTech() {
        String value = readOneLine(BATTERY_TECH_PATH);
        return value;
    }
     @Override
    public String getPreferenceKey() {
        return KEY_BATTERY_TECH;
    }
}