对接一个第三方应用做调试时，想打印出所有的配置，调试我这边做的配置是否有效，摸索了一番后找到了一个解决方案，废话不多说，直接上代码。

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package com.marioplus;

import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
import org.springframework.core.env.ConfigurableEnvironment;
import org.springframework.core.env.EnumerablePropertySource;
import org.springframework.core.env.MutablePropertySources;

import javax.annotation.Resource;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.Map;
import java.util.function.Function;
import java.util.stream.Collectors;

@Slf4j
@SpringBootApplication
public class App extends SpringBootServletInitializer implements CommandLineRunner {

    @Resource
    private ConfigurableEnvironment springEnv;

    public static void main(String[] args) {
        SpringApplication.run(App.class, args);
    }

    @Override
    public void run(String... args) throws Exception {
        MutablePropertySources propSrcs = springEnv.getPropertySources();
        //  // 获取所有配置 key -> [source, key, value]
        Map<String, String[]> props = propSrcs.stream()
                .filter(ps -> ps instanceof EnumerablePropertySource)
                .map(ps -> (EnumerablePropertySource<?>) ps)
                .flatMap(ps -> {
                            String psName = ps.getName();
                            if (psName.startsWith("applicationConfig")) {
                                psName = psName.substring(31);
                                psName = psName.substring(0, psName.length() - 1);
                            }
                            final String fpsName = psName;
                            return Arrays.stream(ps.getPropertyNames())
                                    .map(ppName -> new String[]{fpsName, ppName, springEnv.getProperty(ppName)});
                        }
                )
                .distinct()
                .sorted(Comparator.comparing(pArr -> pArr[1]))
                .collect(Collectors.toMap(pArr -> pArr[1], Function.identity(), (pArr1, pArr2) -> pArr1));

        // key 和 value 之间的最小间隙
        int interval = 20;
        int max01 = props.values().stream()
                .map(pArr -> pArr[0])
                .max(Comparator.comparingInt(String::length))
                .orElse("")
                .length();
        int max12 = props.values().stream()
                .map(pArr -> pArr[1])
                .max(Comparator.comparingInt(String::length))
                .orElse("")
                .length();

        // 打印
        String propStr = props.entrySet().stream()
                .sorted(Map.Entry.comparingByKey())
                .map(e -> {
                    String[] pArr = e.getValue();
                    int i01 = max01 - pArr[0].length() + interval;
                    int i12 = max12 - pArr[1].length() + interval;
                    String p01 = String.join("", Collections.nCopies(i01, " "));
                    String p12 = String.join("", Collections.nCopies(i12, " "));
                    return pArr[0] + p01 + pArr[1] + p12 + pArr[2];
                })
                .reduce((s1, s2) -> s1 + "\n" + s2)
                .orElse("");
        log.debug("开始输出环境变量");
        log.debug("\n" + propStr);
        log.debug("环境变量输出完毕");
    }
}