需要配置一個spring 啟動時的事件監聽器.

SpringRootAppInitListener.java

配置類

    /**
     * spring 根容器啟動時的監聽事件
     *
     * @return ApplicationContextInitializer<?>[]
     */
    @Override
    protected ApplicationContextInitializer<?>[] getRootApplicationContextInitializers() {
        SpringRootAppInitListener springRootAppInitListener = new
 
 SpringRootAppInitListener();
        return new ApplicationContextInitializer[]{springRootAppInitListener};
    }

實現方式

public class SpringRootAppInitListener implements ApplicationContextInitializer {

    private static final Logger logger = LoggerFactory.getLogger(SpringRootAppInitListener.class);

    private
 
 static final String DEFAULT_CONFIG_PREFIX = "application";

    private static final String DEFAULT_CONFIG_SUFFIX = ".properties";

    private static final String DEFAULT_CONFIG_DELIMITE = "-";

    private static final String DEFAULT_CONFIG_KEY = "spring.active.profile";


    @Override
    public
 
 void initialize(ConfigurableApplicationContext applicationContext) {
        MutablePropertySources sources = applicationContext.getEnvironment().getPropertySources();
        //載入預設的配置檔案
        PropertiesLoader propertiesLoader = new PropertiesLoader(DEFAULT_CONFIG_PREFIX + DEFAULT_CONFIG_SUFFIX);
        Properties defaultProperties = propertiesLoader.getProperties();
        //獲取要載入的配置檔案的字尾名稱
        String suFix = defaultProperties.getProperty(DEFAULT_CONFIG_KEY);

        //載入配置檔案
        Properties properties = null;
        if (!StringUtil.isEmpty(suFix)) {
            properties = propertiesLoader.loadClassPathProperties(DEFAULT_CONFIG_PREFIX + DEFAULT_CONFIG_DELIMITE + suFix + DEFAULT_CONFIG_SUFFIX);
        }
        //兩個配置檔案合併
        propertiesLoader.mergerProperties(defaultProperties, properties);
        //載入到spring 的配置中去
        sources.addFirst(new PropertiesPropertySource(DEFAULT_CONFIG_PREFIX, properties));
        logger.info("spring root init!");
    }
}

PropertiesLoader.java

public class PropertiesLoader {
    private static Logger logger = LoggerFactory.getLogger(PropertiesLoader.class);

    private static ResourceLoader resourceLoader = new DefaultResourceLoader();

    private final Properties properties;

    public PropertiesLoader(String... resourcesPaths) {
        properties = loadProperties(resourcesPaths);
    }

    public Properties getProperties() {
        return properties;
    }

    /**
     * 取出Property，但以System的Property優先,取不到返回空字串.
     */
    private String getValue(String key) {
        String systemProperty = System.getProperty(key);
        if (systemProperty != null) {
            return systemProperty;
        }
        if (properties.containsKey(key)) {
            return properties.getProperty(key);
        }
        return "";
    }

    /**
     * 取出String型別的Property，但以System的Property優先,如果都為Null則丟擲異常.
     */
    public String getProperty(String key) {
        String value = getValue(key);
        if (value == null) {
            throw new NoSuchElementException();
        }
        return value;
    }

    /**
     * 取出String型別的Property，但以System的Property優先.如果都為Null則返回Default值.
     */
    public String getProperty(String key, String defaultValue) {
        String value = getValue(key);
        return value != null ? value : defaultValue;
    }

    /**
     * 取出Integer型別的Property，但以System的Property優先.如果都為Null或內容錯誤則丟擲異常.
     */
    public Integer getInteger(String key) {
        String value = getValue(key);
        if (value == null) {
            throw new NoSuchElementException();
        }
        return Integer.valueOf(value);
    }

    /**
     * 取出Integer型別的Property，但以System的Property優先.如果都為Null則返回Default值，如果內容錯誤則丟擲異常
     */
    public Integer getInteger(String key, Integer defaultValue) {
        String value = getValue(key);
        return value != null ? Integer.valueOf(value) : defaultValue;
    }

    /**
     * 取出Double型別的Property，但以System的Property優先.如果都為Null或內容錯誤則丟擲異常.
     */
    public Double getDouble(String key) {
        String value = getValue(key);
        if (value == null) {
            throw new NoSuchElementException();
        }
        return Double.valueOf(value);
    }

    /**
     * 取出Double型別的Property，但以System的Property優先.如果都為Null則返回Default值，如果內容錯誤則丟擲異常
     */
    public Double getDouble(String key, Integer defaultValue) {
        String value = getValue(key);
        return value != null ? Double.valueOf(value) : defaultValue;
    }

    /**
     * 取出Boolean型別的Property，但以System的Property優先.如果都為Null丟擲異常,如果內容不是true/false則返回false.
     */
    public Boolean getBoolean(String key) {
        String value = getValue(key);
        if (value == null) {
            throw new NoSuchElementException();
        }
        return Boolean.valueOf(value);
    }

    /**
     * 取出Boolean型別的Property，但以System的Property優先.如果都為Null則返回Default值,如果內容不為true/false則返回false.
     */
    public Boolean getBoolean(String key, boolean defaultValue) {
        String value = getValue(key);
        return value != null ? Boolean.valueOf(value) : defaultValue;
    }

    /**
     * 載入多個檔案, 檔案路徑使用Spring Resource格式.
     */
    private Properties loadProperties(String... resourcesPaths) {
        Properties props = new Properties();

        for (String location : resourcesPaths) {

            InputStream is = null;
            try {
                Resource resource = resourceLoader.getResource(location);
                is = resource.getInputStream();
                props.load(is);
            } catch (IOException ex) {
                logger.info("Could not load properties from path:" + location + ", " + ex.getMessage());
            } finally {
                IOUtils.closeQuietly(is);
            }
        }
        return props;
    }

    /**
     * 載入多個檔案 classpath 檔案
     */
    public Properties loadClassPathProperties(String resourcesPaths) {
        Properties props = new Properties();
        Resource resource = new ClassPathResource(resourcesPaths);
        InputStream is = null;
        try {
            is = resource.getInputStream();
            props.load(is);
        } catch (IOException ex) {
            logger.info("Could not load properties from path:" + resourcesPaths + ", " + ex.getMessage());
        } finally {
            IOUtils.closeQuietly(is);
        }
        return props;
    }

    /**
     * 合併兩個配置
     *
     * @param source source
     * @param dist   dist
     */
    public void mergerProperties(Properties source, Properties dist) {
        Enumeration enum1 = source.propertyNames();//得到配置檔案的名字
        while (enum1.hasMoreElements()) {
            Object strKey = enum1.nextElement();
            Object value = source.get(strKey);
            dist.put(strKey, value);
        }
    }
}

配置方式

resources
    application.properties
    application-dev.properties
    application-prod.properties
    application-test.properties

配置方式

在application.properties 配置
    spring.active.profile=dev // 啟用不同的環境