classpath文件加载进内存

java方式

this.getClass().getClassLoader().getResourceAsStream()

InputStream resourceAsStream = this.getClass().getClassLoader().getResourceAsStream("application.properties");
//转Properties对象
Properties properties = new Properties();
properties.load(resourceAsStream);

spring方式

ClassPathResource 

ClassPathResource classPathResource = new ClassPathResource("application.properties");
InputStream inputStream = classPathResource.getInputStream();