Reading a properties file using design patterns

I am trying to read properties file using a singleton class. I would like to know if there are any best practices and design patterns to read the properties file. I found dependency injection is one way to read properties file. But, I did not find any examples on the DI design pattern. Any sample code and links would be helpful.

package com.cisco.propertiesreader;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
import java.util.Set;

import org.apache.log4j.Logger;

public class ReadProperties {

    private static final Logger LOGGER = Logger.getLogger(ReadProperties.class);

    private final Properties props = new Properties();

    private ReadProperties() {
        InputStream in = this.getClass().getClassLoader().getResourceAsStream("config.properties");
        try {
            props.load(in);
        } catch (IOException e) {
            LOGGER.error(e.getMessage());
        }
    }

    private static class PropHolder {
        private static final ReadProperties INSTANCE = new ReadProperties();
    }

    public static ReadProperties getInstance() {
        return PropHolder.INSTANCE;
    }

    public String getProperty(String key) {
        return props.getProperty(key);
    }

    public Set<String> getAllPropertyNames() {
        return props.stringPropertyNames();
    }

    public boolean containsKey(String key) {
        return props.containsKey(key);
    }
}