Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright 2012 Eng Kam Hon (kamhon@gmail.com)
 * 
 * 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.
 */

import java.util.Arrays;
import java.util.Collection;

import java.util.Iterator;

import java.util.Map;

public class Main {
    /**
     * Make the log more meanings
     * 
     * @param <K>
     * @param <V>
     * @param map
     * @return
     */
    public static <K, V> String toLog(Map<K, V> map) {
        // using StringBuffer instead of String because expect there are many append operation
        StringBuffer sb = new StringBuffer();

        if (map == null) {
            return null;
        }
        if (map.isEmpty()) {
            return map.toString();
        }

        sb.append("{");

        for (Iterator<K> iterator = map.keySet().iterator(); iterator.hasNext();) {
            K key = iterator.next();
            Object value = map.get(key);
            sb.append(key).append("=");
            sb.append(toString4Log(value));
            if (iterator.hasNext()) {
                sb.append(", ");
            }
        }

        sb.append("}");

        return sb.toString();
    }

    public static <E> String toLog(Collection<E> collec) {
        return toLog("", collec);
    }

    /**
     * Make the log more meanings
     * 
     * @param <E>
     * @param collec
     * @return
     */
    public static <E> String toLog(String separator, Collection<E> collec) {
        // using StringBuffer instead of String because expect there are many append operation
        StringBuffer sb = new StringBuffer();

        if (collec == null) {
            return null;
        }
        if (collec.isEmpty()) {
            return collec.toString();
        }
        sb.append("[");
        for (Iterator<E> iterator = collec.iterator(); iterator.hasNext();) {
            E value = iterator.next();
            sb.append(separator).append(toString4Log(value)).append(separator);
            if (iterator.hasNext()) {
                sb.append(", ");
            }
        }

        sb.append("]");
        return sb.toString();
    }

    public static <E> String toLog(E... array) {
        return toLog("", array);
    }

    public static <E> String toLog(String separator, E... array) {
        if (array != null)
            return toLog(separator, Arrays.asList(array));
        else
            return null;
    }

    /**
     * true if collection is null or empty.
     * 
     * @param collection
     */
    public static boolean isEmpty(Collection<?> collection) {
        return collection == null || collection.isEmpty();
    }

    private static String toString4Log(Object value) {
        if (value == null) {
            return null;
        } else if (value instanceof String) {
            return (String) value;
        } else if (value instanceof Short) {
            return "" + ((Short) value).shortValue();
        } else if (value instanceof Integer) {
            return "" + ((Integer) value).intValue();
        } else if (value instanceof Long) {
            return "" + ((Long) value).longValue();
        } else if (value instanceof Float) {
            return "" + ((Float) value).floatValue();
        } else if (value instanceof Double) {
            return "" + ((Double) value).doubleValue();
        } else if (value instanceof Object[]) {
            Object[] objs = (Object[]) value;
            StringBuffer sb = new StringBuffer();
            sb.append("[");
            for (int i = 0; i < objs.length; i++) {
                sb.append(toString4Log(objs[i]));

                if (i != objs.length - 1) {
                    sb.append(", ");
                }
            }
            sb.append("]");
            return sb.toString();
        } else if (value instanceof Iterator) {
            StringBuffer sb = new StringBuffer();
            sb.append("[");
            for (Iterator<?> i = (Iterator<?>) value; i.hasNext();) {
                sb.append(toString4Log(i.next()));
                if (i.hasNext()) {
                    sb.append(", ");
                }
            }
            sb.append("]");
            return sb.toString();
        } else
            return value.toString();
    }
}