Java Properties Load from File loadPropertiesFile(File file, boolean critical)

Description

load Properties File

License

Apache License

Declaration

public static Properties loadPropertiesFile(File file, boolean critical) throws IOException 

Method Source Code

//package com.java2s;
/*//  w w  w.  ja  v a 2s.  c om
 * 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.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;

import java.util.Enumeration;

import java.util.Properties;
import java.util.StringTokenizer;

public class Main {
    private static final String INCLUDES_PROPERTY = "${includes}";
    private static final String OPTIONALS_PROPERTY = "${optionals}";

    public static Properties loadPropertiesFile(File file, boolean critical) throws IOException {
        // Read the properties file.
        Properties configProps = new Properties();
        InputStream is = null;
        try {
            is = new FileInputStream(file);
            configProps.load(is);
        } catch (FileNotFoundException ex) {
            if (critical) {
                throw ex;
            }
        } catch (IOException ex) {
            System.err.println("Error loading properties from " + file);
            return null;
        } finally {
            if (is != null) {
                try {
                    is.close();
                } catch (Exception e) {
                }
            }
        }

        loadIncludes(INCLUDES_PROPERTY, true, file, configProps);
        loadIncludes(OPTIONALS_PROPERTY, false, file, configProps);

        return configProps;
    }

    private static void loadIncludes(String propertyName, boolean mandatory, File file, Properties configProps)
            throws IOException {
        String includes = configProps.getProperty(propertyName);
        if (includes != null) {
            StringTokenizer st = new StringTokenizer(includes, "\" ", true);
            if (st.countTokens() > 0) {
                String location;
                do {
                    location = nextLocation(st);
                    if (location != null) {
                        File newLocation = new File(location);
                        if (!newLocation.isAbsolute()) {
                            newLocation = new File(file.getParent(), location);
                        }
                        Properties props = loadPropertiesFile(newLocation, true);
                        // included properties do NOT override current values
                        for (Enumeration<?> e = props.propertyNames(); e.hasMoreElements();) {
                            String name = (String) e.nextElement();
                            if (!configProps.containsKey(name)) {
                                configProps.put(name, props.getProperty(name));
                            }
                        }
                    }
                } while (location != null);
            }
        }
        configProps.remove(propertyName);
    }

    private static String nextLocation(StringTokenizer st) {
        String retVal = null;

        if (st.countTokens() > 0) {
            String tokenList = "\" ";
            StringBuffer tokBuf = new StringBuffer(10);
            String tok;
            boolean inQuote = false;
            boolean tokStarted = false;
            boolean exit = false;
            while ((st.hasMoreTokens()) && (!exit)) {
                tok = st.nextToken(tokenList);
                if (tok.equals("\"")) {
                    inQuote = !inQuote;
                    if (inQuote) {
                        tokenList = "\"";
                    } else {
                        tokenList = "\" ";
                    }

                } else if (tok.equals(" ")) {
                    if (tokStarted) {
                        retVal = tokBuf.toString();
                        tokStarted = false;
                        tokBuf = new StringBuffer(10);
                        exit = true;
                    }
                } else {
                    tokStarted = true;
                    tokBuf.append(tok.trim());
                }
            }

            // Handle case where end of token stream and
            // still got data
            if ((!exit) && (tokStarted)) {
                retVal = tokBuf.toString();
            }
        }

        return retVal;
    }
}

Related

1. loadProperties(String propertiesFile)
2. loadProperties(String propertyFile)
3. loadProperties(String propertyPath)
4. loadProperties(String propsFile)
5. loadProperties(String sFile)
6. loadPropertiesFile(final File file)
7. loadPropertiesFile(String fileName)
8. loadPropertiesFile(String fileName)
9. loadPropertiesFile(String filePath)