CachedPropertiesProvider.java

package krasa.formatter.settings.provider;

import java.io.File;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;

import krasa.formatter.common.ModifiableFile;
import krasa.formatter.plugin.InvalidPropertyFile;
import krasa.formatter.utils.FileUtils;

/**
 * @author Vojtech Krasa
 */
public class CachedPropertiesProvider extends CachedProvider<Properties> {

	protected CachedPropertiesProvider(ModifiableFile modifiableFile) {
		super(modifiableFile);
	}

	/**
	 * Return a Java Properties object representing the options that are in the specified configuration file.
	 */
	@Override
	protected Properties readFile(File file) throws InvalidPropertyFile {
		final Properties formatterOptions = FileUtils.readPropertiesFile(file, createDefaultConfig());
		// Properties.load() does not trim trailing whitespace from prop values, so trim it ourselves, since it would
		// cause the Eclipse formatter to fail to parse the values.
		trimTrailingWhitespaceFromConfigValues(formatterOptions);
		validateConfig(formatterOptions, file);
		return formatterOptions;
	}

	protected Properties readXmlFile(File file, String profile) {
		final Properties formatterOptions = FileUtils.readXmlJavaSettingsFile(file, createDefaultConfig(), profile);
		trimTrailingWhitespaceFromConfigValues(formatterOptions);
		validateConfig(formatterOptions, file);
		return formatterOptions;
	}

	protected void trimTrailingWhitespaceFromConfigValues(Properties config) {
		// First trim the values and store the trimmed values in a temporary map.
		Map<String, String> map = new HashMap<String, String>(config.size());
		for (Object key : config.keySet()) {
			String optionName = (String) key;
			String optionValue = config.getProperty(optionName);
			map.put(optionName, (optionValue != null) ? optionValue.trim() : null);
		}
		// Then copy the values back to the original Properties object.
		for (String key : map.keySet()) {
			config.setProperty(key, map.get(key));
		}
	}

	protected void validateConfig(Properties config, File file) {
		if (config.isEmpty()) {
			throw new InvalidPropertyFile(file);
		}
	}

	protected Properties createDefaultConfig() {
		return new Properties();
	}

}