Guava学习：Joiner和Splitter工具（二）

测试类：

package com.example.demo;

import java.util.Arrays;
import java.util.List;

import org.assertj.core.internal.Characters;

import com.google.common.base.Joiner;
import com.google.common.base.Splitter;
import com.google.common.collect.Lists;
import com.google.common.primitives.Booleans;
import com.google.common.primitives.Chars;
import com.google.common.primitives.Doubles;
import com.google.common.primitives.Floats;
import com.google.common.primitives.Ints;

/**
 * @author zero 2019/02/23
 */
public class GuavaExample {

    public static void main(String[] args) {
        System.out.println("Guava excesice.");

        // testGuavaCommonUseMethod();
        // testGuavaSplitterAllTypeMethod();
        testGuavaJoinerAllTypeMethod();
    }

    // 测试1：初步
    public static void testGuavaCommonUseMethod() {
        String string = "a,bb,ccc,dddd";
        String[] strings = {"a", "b", "c"};

        // 数组需要进行转换成list集合比较安全，当然也可以直接join
        String newStrings = Joiner.on("-").join(Arrays.asList(strings));
        System.out.println(newStrings);

        Iterable<String> newString2 = Splitter.on(",").split(string);
        newString2.forEach(System.out::println);
        System.out.println(newString2);
    }

    // Test Splitter Method
    public static void testGuavaSplitterAllTypeMethod() {
        String string = "apple,xiaomi,,,honour,,vivo-nex";
        String string2 = "1-2-3-4-5-6";
        // 去掉无用的值
        Iterable<String> usefulString = Splitter.on(",").omitEmptyStrings().trimResults().split(string);
        usefulString.forEach(System.out::println);// apple xiaomi honour vivo-nex

        // fixedLength(3)：表示三个字符三个字符切断促成一个元素。
        Iterable<String> newString2 = Splitter.fixedLength(3).split(string2);
        System.out.println(newString2);// [1-2, -3]
        newString2.forEach(System.out::println);// 1-2 -3- 4-5 -6

        // 遍历字符串的每个字符： 如果含有匹配的字段，则剔除匹配的字段再输出字符；如果没匹配上，则输出元字符。
        Iterable<String> patternString = Splitter.onPattern("-").split(string2);
        System.out.println(patternString);// [1, 2, 3, 4, 5, 6]
    }

    // Test Joiner Method
    public static void testGuavaJoinerAllTypeMethod() {
        String[] strings = {"a", "b", "c"};
        List<Integer> integers = Lists.newArrayList(1, 2, 3, 4, 5, 6, 7);

        String joinStr = Joiner.on('-').join(integers);
        System.out.println(joinStr);

        String joinNewStr = Joiner.on("to").join(integers);
        System.out.println(joinNewStr);

        // Guava对基本类型的支持
        int[] numbers = {1, 2, 3, 4, 5};
        float[] f = {1.0f, 2.00f, 3.000f};
        double[] d = {10.00, 20.12, 0.25};
        char[] c = {'c', 'd', 'a'};
        boolean[] b = {true, false};
        String numStr = Joiner.on(";").join(Ints.asList(numbers));
        System.out.println(numStr);
        String newF = Joiner.on(";").join(Floats.asList(f));
        System.out.println(newF);
        String newD = Joiner.on(";").join(Doubles.asList(d));
        System.out.println(newD);
        String newC = Joiner.on(";").join(Chars.asList(c));
        System.out.println(newC);
        String newB = Joiner.on(";").join(Booleans.asList(b));
        System.out.println(newB);
    }

}

2.测试结果：