Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright (C) 2011 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.
 */

public class Main {
    /**
     * Finds the index of the first word that starts with the given prefix.
     * <p>
     * If not found, returns -1.
     *
     * @param text the text in which to search for the prefix
     * @param prefix the text to find, in upper case letters
     */
    public static int indexOfWordPrefix(CharSequence text, String prefix) {
        if (prefix == null || text == null) {
            return -1;
        }

        int textLength = text.length();
        int prefixLength = prefix.length();

        if (prefixLength == 0 || textLength < prefixLength) {
            return -1;
        }

        int i = 0;
        while (i < textLength) {
            // Skip non-word characters
            while (i < textLength && !Character.isLetterOrDigit(text.charAt(i))) {
                i++;
            }

            if (i + prefixLength > textLength) {
                return -1;
            }

            // Compare the prefixes
            int j;
            for (j = 0; j < prefixLength; j++) {
                if (Character.toUpperCase(text.charAt(i + j)) != prefix.charAt(j)) {
                    break;
                }
            }
            if (j == prefixLength) {
                return i;
            }

            // Skip this word
            while (i < textLength && Character.isLetterOrDigit(text.charAt(i))) {
                i++;
            }
        }

        return -1;
    }
}