Pathmatchingresourcepatternresolver parsing configuration file resource file

Usage method ：

ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();
Resource resource = resourcePatternResolver.getResource("youResourcePath");

If it's not the root path , The path needs to be specified , for example ：

 

From the classpath rules Get... In the directory demo.drl file  

Resource resource = resourcePatternResolver .getResource("rules/demo.drl");

Can be clearly specified classpath Prefix ：

Resource resource = resourcePatternResolver .getResource("classpath:rules/demo.drl");

Use wildcards to get files that meet a certain format

adopt classpath* Prefix specifies to get the specified file from all Classpaths

Resource[] resource = resourcePatternResolver .getResource("classpath*:rules/demo.drl");

obtain rules Prefix under directory is demo The file of

Resource[] resource = resourcePatternResolver .getResource("classpath*:rules/demo*.drl");

  obtain com.a.rules、com.b.rules、com.c.rules In the catalog demo The file of

Resource[] resource = resourcePatternResolver .getResource("classpath*:com/*/rules/demo.drl");

   Two * Represents any multilayer directory

Resource[] resource = resourcePatternResolver .getResource("classpath*:com/**/rules/demo.drl");

Convert the read resource file into a string ：
 

import org.apache.poi.util.IOUtils;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;

import java.io.IOException;

/**
 * @author  Xiang Zhenhua 
 * @date 2022/07/25 10:59
 */
public class ResourceUtils {

    /**
     *  Read the configuration file and convert it into a string 
     *
     * @param path  route ,eg: classpath:META-INF/xxx/spring.factories
     * @return
     */
    public static String read(String path) {
        ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();
        Resource resource = resourcePatternResolver.getResource(path);
        try {
            byte[] bytes = IOUtils.toByteArray(resource.getInputStream());
            return new String(bytes);
        } catch (IOException e) {
            return null;
        }
    }
}