Java Properties Load from File load(InputStream inputStream)

Description

load

License

Apache License

Declaration

public static LinkedHashMap<String, String> load(InputStream inputStream) throws IOException 

Method Source Code

//package com.java2s;
/*/*w w  w.j  a v a2  s. c  o m*/
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 java.io.BufferedReader;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

import java.util.LinkedHashMap;

public class Main {
    private static final String keyValueSeparators = "=: \t\r\n\f";
    private static final String strictKeyValueSeparators = "=:";
    private static final String whiteSpaceChars = " \t\r\n\f";

    public static LinkedHashMap<String, String> load(InputStream inputStream) throws IOException {
        LinkedHashMap<String, String> properties = new LinkedHashMap<String, String>();
        BufferedReader in = new BufferedReader(new InputStreamReader(inputStream));
        while (true) {
            // Get next line
            String line = in.readLine();
            if (line == null)
                return properties;

            if (line.length() > 0) {

                // Find start of key
                int len = line.length();
                int keyStart;
                for (keyStart = 0; keyStart < len; keyStart++)
                    if (whiteSpaceChars.indexOf(line.charAt(keyStart)) == -1)
                        break;

                // Blank lines are ignored
                if (keyStart == len)
                    continue;

                // Continue lines that end in slashes if they are not comments
                char firstChar = line.charAt(keyStart);
                if ((firstChar != '#') && (firstChar != '!')) {
                    while (continueLine(line)) {
                        String nextLine = in.readLine();
                        if (nextLine == null)
                            nextLine = "";
                        String loppedLine = line.substring(0, len - 1);
                        // Advance beyond whitespace on new line
                        int startIndex;
                        for (startIndex = 0; startIndex < nextLine.length(); startIndex++)
                            if (whiteSpaceChars.indexOf(nextLine.charAt(startIndex)) == -1)
                                break;
                        nextLine = nextLine.substring(startIndex, nextLine.length());
                        line = loppedLine + nextLine;
                        len = line.length();
                    }

                    // Find separation between key and value
                    int separatorIndex;
                    for (separatorIndex = keyStart; separatorIndex < len; separatorIndex++) {
                        char currentChar = line.charAt(separatorIndex);
                        if (currentChar == '\\')
                            separatorIndex++;
                        else if (keyValueSeparators.indexOf(currentChar) != -1)
                            break;
                    }

                    // Skip over whitespace after key if any
                    int valueIndex;
                    for (valueIndex = separatorIndex; valueIndex < len; valueIndex++)
                        if (whiteSpaceChars.indexOf(line.charAt(valueIndex)) == -1)
                            break;

                    // Skip over one non whitespace key value separators if any
                    if (valueIndex < len)
                        if (strictKeyValueSeparators.indexOf(line.charAt(valueIndex)) != -1)
                            valueIndex++;

                    // Skip over white space after other separators if any
                    while (valueIndex < len) {
                        if (whiteSpaceChars.indexOf(line.charAt(valueIndex)) == -1)
                            break;
                        valueIndex++;
                    }
                    String key = line.substring(keyStart, separatorIndex);
                    String value = (separatorIndex < len) ? line.substring(valueIndex, len) : "";

                    // Convert then store key and value
                    key = loadConvert(key);
                    value = loadConvert(value);
                    properties.put(key, value);
                }
            }
        }
    }

    private static boolean continueLine(String line) {
        int slashCount = 0;
        int index = line.length() - 1;
        while ((index >= 0) && (line.charAt(index--) == '\\'))
            slashCount++;
        return (slashCount % 2 != 0);
    }

    private static String loadConvert(String theString) {
        char aChar;
        int len = theString.length();
        StringBuffer outBuffer = new StringBuffer(len);

        for (int x = 0; x < len;) {
            aChar = theString.charAt(x++);
            if (aChar == '\\') {
                aChar = theString.charAt(x++);
                if (aChar == 'u') {
                    // Read the xxxx
                    int value = 0;
                    for (int i = 0; i < 4; i++) {
                        aChar = theString.charAt(x++);
                        switch (aChar) {
                        case '0':
                        case '1':
                        case '2':
                        case '3':
                        case '4':
                        case '5':
                        case '6':
                        case '7':
                        case '8':
                        case '9':
                            value = (value << 4) + aChar - '0';
                            break;
                        case 'a':
                        case 'b':
                        case 'c':
                        case 'd':
                        case 'e':
                        case 'f':
                            value = (value << 4) + 10 + aChar - 'a';
                            break;
                        case 'A':
                        case 'B':
                        case 'C':
                        case 'D':
                        case 'E':
                        case 'F':
                            value = (value << 4) + 10 + aChar - 'A';
                            break;
                        default:
                            throw new IllegalArgumentException("Malformed \\uxxxx encoding.");
                        }
                    }
                    outBuffer.append((char) value);
                } else {
                    if (aChar == 't')
                        aChar = '\t';
                    else if (aChar == 'r')
                        aChar = '\r';
                    else if (aChar == 'n')
                        aChar = '\n';
                    else if (aChar == 'f')
                        aChar = '\f';
                    outBuffer.append(aChar);
                }
            } else
                outBuffer.append(aChar);
        }
        return outBuffer.toString();
    }
}

Related

1. load(final Class key, final String env, final Properties defaults)
2. load(final Properties props, final Properties toLoad)
3. load(final String folder, final String fileName)
4. load(InputStream in)
5. load(InputStream input)
6. load(InputStream is)
7. load(InputStream stream)
8. load(Map map, String fileName)
9. load(Properties properties, String fileName)