JpaUnitContext.java 文件源码

private static Map<String, Object> getPersistenceContextProperties(final PersistenceContext persistenceContext) {
    final Map<String, Object> properties = new HashMap<>();
    for (final PersistenceProperty property : persistenceContext.properties()) {
        String propertyValue = property.value();
        Matcher matcher = PROPERTY_PATTERN.matcher(propertyValue);

        while(matcher.find()) {
            String p = matcher.group();
            String systemProperty = p.substring(2, p.length() - 1);
            propertyValue = propertyValue.replace(p, System.getProperty(systemProperty, p));
        }

        properties.put(property.name(), propertyValue);
    }
    return properties;
}