core: Abstract wrappers to deduplicate code + allow to convert commen…

…ted configurations

core/src/main/java/com/electronwill/nightconfig/core/conversion/AbstractConvertedConfig.java

@@ -0,0 +1,48 @@
+package com.electronwill.nightconfig.core.conversion;
+
+import com.electronwill.nightconfig.core.Config;
+import com.electronwill.nightconfig.core.utils.ConfigWrapper;
+import com.electronwill.nightconfig.core.utils.TransformingMap;
+import java.util.List;
+import java.util.Map;
+import java.util.function.Function;
+import java.util.function.Predicate;
+
+/**
+ * @author TheElectronWill
+ */
+abstract class AbstractConvertedConfig<C extends Config> extends ConfigWrapper<C>
+		implements Config {
+	final Function<Object, Object> readConversion, writeConversion;
+	final Predicate<Class<?>> supportPredicate;
+
+	AbstractConvertedConfig(C config, Function<Object, Object> readConversion,
+								   Function<Object, Object> writeConversion,
+								   Predicate<Class<?>> supportPredicate) {
+		super(config);
+		this.readConversion = readConversion;
+		this.writeConversion = writeConversion;
+		this.supportPredicate = supportPredicate;
+	}
+
+	@Override
+	public <T> T setValue(List<String> path, Object value) {
+		return (T)readConversion.apply(config.setValue(path, writeConversion.apply(value)));
+	}
+
+	@Override
+	public Map<String, Object> valueMap() {
+		return new TransformingMap<>(config.valueMap(), readConversion, writeConversion,
+									 writeConversion);
+	}
+
+	@Override
+	public <T> T getValue(List<String> path) {
+		return (T)readConversion.apply(config.getValue(path));
+	}
+
+	@Override
+	public boolean supportsType(Class<?> type) {
+		return supportPredicate.test(type);
+	}
+}

core/src/main/java/com/electronwill/nightconfig/core/conversion/CommentedConvertedConfig.java

@@ -0,0 +1,102 @@
+package com.electronwill.nightconfig.core.conversion;
+
+import com.electronwill.nightconfig.core.CommentedConfig;
+import com.electronwill.nightconfig.core.utils.TransformingSet;
+import java.util.List;
+import java.util.Set;
+import java.util.function.Function;
+import java.util.function.Predicate;
+
+/**
+ * A Config's wrapper that converts the values that are read from and put into the config.
+ *
+ * @author TheElectronWill
+ */
+public final class CommentedConvertedConfig extends AbstractConvertedConfig<CommentedConfig>
+		implements CommentedConfig {
+	/**
+	 * Creates a new ConvertedConfig that uses two conversion tables.
+	 *
+	 * @param config           the config to wrap
+	 * @param readTable        the ConversionTable used for parse operations (like getValue)
+	 * @param writeTable       the ConversionTable used for write operations (like setValue)
+	 * @param supportPredicate a Predicate that checks if a given class is supported by the
+	 *                         ConvertedConfig
+	 */
+	public CommentedConvertedConfig(CommentedConfig config, ConversionTable readTable,
+									ConversionTable writeTable,
+									Predicate<Class<?>> supportPredicate) {
+		this(config, readTable::convert, writeTable::convert, supportPredicate);
+	}
+
+	/**
+	 * Creates a new ConvertedConfig that uses two custom conversion functions.
+	 *
+	 * @param config           the config to wrap
+	 * @param readConversion   the Function used for parse operations (like getValue)
+	 * @param writeConversion  the Function used for write operations (like setValue)
+	 * @param supportPredicate a Predicate that checks if a given class is supported by the
+	 *                         ConvertedConfig
+	 */
+	public CommentedConvertedConfig(CommentedConfig config, Function<Object, Object> readConversion,
+									Function<Object, Object> writeConversion,
+									Predicate<Class<?>> supportPredicate) {
+		super(config, readConversion, writeConversion, supportPredicate);
+	}
+
+	@Override
+	public String getComment(List<String> path) {
+		return config.getComment(path);
+	}
+
+	@Override
+	public boolean containsComment(List<String> path) {
+		return config.containsComment(path);
+	}
+
+	@Override
+	public String setComment(List<String> path, String comment) {
+		return config.setComment(path, comment);
+	}
+
+	@Override
+	public void removeComment(List<String> path) {
+		config.removeComment(path);
+	}
+
+	@Override
+	public Set<? extends CommentedConfig.Entry> entrySet() {
+		Function<CommentedConfig.Entry, CommentedConfig.Entry> readTransfo = entry -> new CommentedConfig.Entry() {
+			@Override
+			public String getComment() {
+				return entry.getComment();
+			}
+
+			@Override
+			public String setComment(String comment) {
+				return entry.setComment(comment);
+			}
+
+			@Override
+			public void removeComment() {
+				entry.removeComment();
+			}
+
+			@Override
+			public String getKey() {
+				return entry.getKey();
+			}
+
+			@Override
+			public <T> T getValue() {
+				return (T)readConversion.apply(entry.getValue());
+			}
+
+			@Override
+			public <T> T setValue(Object value) {
+				return (T)readConversion.apply(entry.setValue(writeConversion.apply(value)));
+			}
+		};
+		return new TransformingSet<>(config.entrySet(), readTransfo, o -> null, e -> e);
+	}
+}