Playing with jakarta commons configuration, reading external files

custom-conf_pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>com.github.alexvictoor</groupId>
  <artifactId>custom-conf</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>custom-conf</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>

  <dependencies>
      <dependency>
          <groupId>commons-configuration</groupId>
          <artifactId>commons-configuration</artifactId>
          <version>1.10</version>
      </dependency>
      <dependency>
          <groupId>com.google.guava</groupId>
          <artifactId>guava</artifactId>
          <version>18.0</version>
      </dependency>
      <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>
      <dependency>
          <groupId>org.assertj</groupId>
          <artifactId>assertj-core</artifactId>
          <version>1.7.0</version>
          <scope>test</scope>
      </dependency>
  </dependencies>
</project>

custom-conf_src_main_java_com_github_alexvictoor_SingleExternalFileConfiguration.java

package com.github.alexvictoor;


import com.google.common.base.Throwables;
import com.google.common.io.Files;
import org.apache.commons.configuration.ConfigurationException;
import org.apache.commons.configuration.PropertiesConfiguration;
import org.apache.commons.configuration.reloading.FileChangedReloadingStrategy;

import java.io.File;
import java.io.IOException;
import java.io.Reader;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.nio.charset.Charset;

public class SingleExternalFileConfiguration extends PropertiesConfiguration{

    private File file;

    public SingleExternalFileConfiguration(URL url) throws ConfigurationException, URISyntaxException {
        super(url);
        setReloadingStrategy(new CustomReloadStrategy());
    }

    @Override
    public synchronized void load(Reader in) throws ConfigurationException {
        super.load(in);
        String fileKey = getKeys().next();
        String filePath = getString(fileKey);
        try {
            URI uri = new URI(getBasePath() + filePath);
            file = new File(uri);
            String content = Files.toString(file, Charset.defaultCharset());
            addProperty("content." + fileKey, content);
        } catch (IOException e) {
            throw Throwables.propagate(e);
        } catch (URISyntaxException e) {
            throw Throwables.propagate(e);
        }
    }

    public class CustomReloadStrategy extends FileChangedReloadingStrategy {
        @Override
        protected File getFile() {
            return file;
        }
    }
}

custom-conf_src_test_java_com_github_alexvictoor_SingleExternalFileConfigurationTest.java

package com.github.alexvictoor;


import org.apache.commons.configuration.Configuration;
import org.junit.Test;

import java.net.URL;

import static org.assertj.core.api.Assertions.assertThat;

public class SingleExternalFileConfigurationTest {

    @Test
    public void should_load_file() throws Exception {
        // given
        URL url = getClass().getResource("/conf.properties");
        Configuration configuration = new SingleExternalFileConfiguration(url);
        // when
        String content = configuration.getString("content.my.file.conf");
        // then
        assertThat(content).isEqualTo("Coucou");

        /*
        Integer lock = new Integer(0);
        synchronized (lock) {
            for (int i=0; i<100; i++)  {
                lock.wait(1000);
                System.out.println(configuration.getString("content.my.file.conf"));
            }
        }*/
    }
}

custom-conf_src_test_resources_conf.properties

my.file.conf=toto.txt

custom-conf_src_test_resources_toto.txt

Coucou