Add doc

formats/properties/commonMain/src/kotlinx/serialization/properties/Properties.kt

@@ -26,7 +26,7 @@ import kotlinx.serialization.modules.*
  * @Serializable
  * class DataHolder(val data: Data, val property2: String)
  *
- * val map = Properties.store(DataHolder(Data("value1"), "value2"))
+ * val map = Properties.encodeToMap(DataHolder(Data("value1"), "value2"))
  * // map contents will be the following:
  * // property2 = value2
  * // data.property1 = value1

formats/properties/commonMain/src/kotlinx/serialization/properties/StringProperties.kt

@@ -10,19 +10,64 @@ import kotlinx.serialization.encoding.*
 import kotlinx.serialization.internal.*
 import kotlinx.serialization.modules.*
 
+/**
+ * Transforms a [Serializable] class' properties into a single flat [String] representing the class data
+ * in the properties format.
+ *
+ * If the given class has non-primitive property `d` of arbitrary type `D`, `D` values are inserted
+ * into the same map; keys for such values are prefixed with string `d.`:
+ *
+ * ```
+ * @Serializable
+ * class Data(val property1: String)
+ *
+ * @Serializable
+ * class DataHolder(val data: Data, val property2: String)
+ *
+ * val string = StringProperties.encodeToString(properties)
+ * // string contents will be the following:
+ * """
+ *     property2 = value2
+ *     data.property1 = value1
+ * """
+ * ```
+ *
+ * If the given class has a [List] property `l`, each value from the list
+ * would be prefixed with `l.N.`, where N is an index for a particular value.
+ * [Map] is treated as a `[key,value,...]` list.
+
+ * Conversely, this class can convert a properties string into a [Serializable] class instance.
+ * ```
+ * @Serializable
+ * class Data(val property1: String)
+ *
+ * @Serializable
+ * class DataHolder(val data: Data, val property2: String)
+ *
+ * val string = """
+ *     property2 = value2
+ *     data.property1 = value1
+ * """
+ * val data = StringProperties.decodeToString(string, DataHolder.serializer())
+ * // data contents will be the following:
+ * // DataHolder(data = Data(property1 = "value1"), property2 = "value2")
+ * ```
+ * 
+ * @param conf A [PropertiesConf] which contain configuration for customising the output string.
+ */
 @ExperimentalSerializationApi
 @Suppress("UNUSED_PARAMETER")
 public sealed class StringProperties(
     private val conf: PropertiesConf,
     private val properties: Properties = Properties(conf.serializersModule),
-) : SerialFormat by properties {
+) : SerialFormat by properties, StringFormat {
 
     /**
      * Encodes properties from the given [value] to a properties String using the given [serializer].
      * `null` values are omitted from the output.
      */
     @ExperimentalSerializationApi
-    public fun <T> encodeToString(serializer: SerializationStrategy<T>, value: T): String {
+    public override fun <T> encodeToString(serializer: SerializationStrategy<T>, value: T): String {
         val map = properties.encodeToMap(serializer, value)
         val builder = StringBuilder()
         for ((k, v) in map) {
@@ -45,12 +90,10 @@ public sealed class StringProperties(
      * [String] values are converted to respective primitive types using default conversion methods.
      * [T] may contain properties of nullable types; they will be filled by non-null values from the [map], if present.
      */
-    public fun <T> decodeFromString(deserializer: DeserializationStrategy<T>, string: String): T {
+    public override fun <T> decodeFromString(deserializer: DeserializationStrategy<T>, string: String): T {
         val result = mutableMapOf<String, String>()
         for (line in string.logicalLines()) {
-            println("line=`$line`")
             val parsedLine = line.unescaped()
-            println("parsedLine=`$parsedLine`")
             var keyEnd = parsedLine.length
             for (i in parsedLine.indices) {
                 if (parsedLine[i] in separators) {
@@ -77,8 +120,6 @@ public sealed class StringProperties(
 
             result[parsedLine.substring(0, keyEnd)] = parsedLine.substring(valueBegin)
         }
-        println(result)
-        println(result.keys)
         return properties.decodeFromStringMap(deserializer, result)
     }
 
@@ -97,8 +138,8 @@ private class StringPropertiesImpl(conf: PropertiesConf) : StringProperties(conf
  * TODO: doc
  */
 @ExperimentalSerializationApi
-public fun StringProperties(builderAction: PropertiesBuilder.() -> Unit = {}): StringProperties {
-    val builder = PropertiesBuilder(PropertiesConf())
+public fun StringProperties(builderAction: StringPropertiesBuilder.() -> Unit = {}): StringProperties {
+    val builder = StringPropertiesBuilder(PropertiesConf())
     builder.builderAction()
     return StringPropertiesImpl(builder.build())
 }
@@ -121,13 +162,40 @@ public inline fun <reified T> StringProperties.encodeToString(value: T): String
 public inline fun <reified T> StringProperties.decodeFromString(propertiesString: String): T =
     decodeFromString(serializersModule.serializer(), propertiesString)
 
+/**
+ * Builder of the [StringProperties] instance provided by `StringProperties { ... }` factory function.
+ */
 @ExperimentalSerializationApi
-public class PropertiesBuilder internal constructor(from: PropertiesConf) {
+public class StringPropertiesBuilder internal constructor(from: PropertiesConf) {
 
+    /**
+     * A [LineSeparator] to be used for separating lines when encoding to a string.
+     * Default value is [LineSeparator.LF].
+     */
     public var lineSeparator: LineSeparator = from.lineSeparator
+
+    /**
+     * A [KeyValueSeparator] to be used for separating keys and values when encoding to a string.
+     * Default value is [KeyValueSeparator.EQUALS].
+     */
     public var keyValueSeparator: KeyValueSeparator = from.keyValueSeparator
+
+    /**
+     * A number of spaces to be inserted before the [keyValueSeparator] when encoding to a string.
+     * Default value is `0`.
+     */
     public var spacesBeforeSeparator: Int = from.spacesBeforeSeparator
+
+    /**
+     * A number of spaces to be inserted after the [keyValueSeparator] when encoding to a string.
+     * Default value is `0`.
+     */
     public var spacesAfterSeparator: Int = from.spacesAfterSeparator
+
+    /**
+     * A [SerializersModule] to be used for encoding and decoding.
+     * Default value is [EmptySerializersModule].
+     */
     public var module: SerializersModule = from.serializersModule
 
     internal fun build(): PropertiesConf {