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HIPPO4J、HIPPO4J-CORE 公共代码库.
There is a newer version: 1.5.0
/*
 * 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.
 */

package cn.hippo4j.common.toolkit;

import java.io.IOException;
import java.util.Arrays;
import java.util.Iterator;
import java.util.Objects;

/**
 * reference google guava
 */
public class Joiner {

    private final String separator;

    private Joiner(String separator) {
        this.separator = Objects.requireNonNull(separator);
    }

    /**
     * Returns a joiner which automatically places {@code separator} between consecutive elements.
     */
    public static Joiner on(String separator) {
        return new Joiner(separator);
    }

    /**
     * Returns a string containing the string representation of each of {@code parts}, using the
     * previously configured separator between each.
     */
    public final String join(Object[] parts) {
        return join(Arrays.asList(parts));
    }

    public final String join(Iterable parts) {
        return join(parts.iterator());
    }

    /**
     * Returns a string containing the string representation of each of {@code parts}, using the
     * previously configured separator between each.
     */
    public final String join(Iterator parts) {
        return appendTo(new StringBuilder(), parts).toString();
    }

    public final StringBuilder appendTo(StringBuilder builder, Iterator parts) {
        try {
            appendTo((Appendable) builder, parts);
        } catch (IOException impossible) {
            throw new AssertionError(impossible);
        }
        return builder;
    }

    public  A appendTo(A appendable, Iterator parts) throws IOException {
        Objects.requireNonNull(appendable);
        if (parts.hasNext()) {
            appendable.append(toString(parts.next()));
            while (parts.hasNext()) {
                appendable.append(separator);
                appendable.append(toString(parts.next()));
            }
        }
        return appendable;
    }

    CharSequence toString(Object part) {
        Objects.requireNonNull(part);
        return (part instanceof CharSequence) ? (CharSequence) part : part.toString();
    }
}