Merge "Make default audio sharing password more secure." into main

import java.lang.annotation.Retention;

import java.lang.annotation.RetentionPolicy;

import java.nio.charset.StandardCharsets;

import java.security.SecureRandom;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Collections;

import java.util.List;

import java.util.Map;

import java.util.Objects;

import java.util.UUID;

import java.util.concurrent.ConcurrentHashMap;

import java.util.concurrent.Executor;

import java.util.concurrent.Executors;

    private static final String SYSUI_PKG = "com.android.systemui";

    private static final String TAG = "LocalBluetoothLeBroadcast";

    private static final boolean DEBUG = BluetoothUtils.D;

    private static final String VALID_PASSWORD_CHARACTERS =

            "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789!@#$%^&*()-_=+[]{}|;:,"

                    + ".<>?/";

    private static final int PASSWORD_LENGTH = 16;

    static final String NAME = "LE_AUDIO_BROADCAST";

    private static final String UNDERLINE = "_";

        mBroadcastId = UNKNOWN_VALUE_PLACEHOLDER;

    }

    private String generateRandomPassword() {

        String randomUUID = UUID.randomUUID().toString();

        // first 16 chars from xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx

        return randomUUID.substring(0, 8) + randomUUID.substring(9, 13) + randomUUID.substring(14,

                18);

    private static String generateRandomPassword() {

        SecureRandom random = new SecureRandom();

        StringBuilder stringBuilder = new StringBuilder(PASSWORD_LENGTH);

        for (int i = 0; i < PASSWORD_LENGTH; i++) {

            int randomIndex = random.nextInt(VALID_PASSWORD_CHARACTERS.length());

            stringBuilder.append(VALID_PASSWORD_CHARACTERS.charAt(randomIndex));

        }

        return stringBuilder.toString();

    }

    private void registerContentObserver() {