common/src/com/android/services/telephony/common/MoreStrings.java

/*
 * Copyright (C) 2013 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.services.telephony.common;

/**
 * Static utility methods for Strings.
 */
public class MoreStrings {

    public static String toSafeString(String value) {
        if (value == null) {
            return null;
        }

        // Do exactly same thing as Uri#toSafeString() does, which will enable us to compare
        // sanitized phone numbers.
        final StringBuilder builder = new StringBuilder();
        for (int i = 0; i < value.length(); i++) {
            final char c = value.charAt(i);
            if (c == '-' || c == '@' || c == '.') {
                builder.append(c);
            } else {
                builder.append('x');
            }
        }
        return builder.toString();
    }

}