Make the VerseContent immutable

Not quite certain this is the way to go, but let's try a functional experiment.

app/src/main/kotlin/org/bspeice/minimalbible/service/format/osisparser/OsisParser.kt

@@ -6,7 +6,6 @@ import java.util.ArrayDeque
 import org.xml.sax.Attributes
 import org.crosswire.jsword.book.OSISUtil
 import org.bspeice.minimalbible.SafeValDelegate
-import kotlin.properties.Delegates
 
 /**
  * Created by bspeice on 9/10/14.
@@ -17,12 +16,12 @@ class OsisParser() : DefaultHandler() {
     // Don't pass a verse as part of the constructor, but still guarantee
     // that it will exist
     public var verse: Verse by SafeValDelegate()
-    val verseContent: VerseContent by Delegates.lazy { VerseContent(verse) }
+    var verseContent: VerseContent? = null
 
     // TODO: Implement a stack to keep min API 8
     val doWrite = ArrayDeque<Boolean>()
 
-    fun getJson() = verseContent.toJson()
+    fun getJson() = verseContent!!.json
 
     override fun startElement(uri: String, localName: String,
                               qName: String, attributes: Attributes) {
@@ -38,6 +37,7 @@ class OsisParser() : DefaultHandler() {
 
     override fun characters(ch: CharArray, start: Int, length: Int) {
         if (doWrite.peek())
-            verseContent.appendContent(String(ch))
+            verseContent = verseContent?.appendContent(String(ch)) ?:
+                    VerseContent(verse, content = String(ch))
     }
 }

app/src/main/kotlin/org/bspeice/minimalbible/service/format/osisparser/VerseContent.kt

@@ -8,26 +8,20 @@ import org.crosswire.jsword.passage.Verse
 import java.util.ArrayList
 
 //TODO: JSON Streaming parsing? http://instagram-engineering.tumblr.com/post/97147584853/json-parsing
-class VerseContent(v: Verse) {
-    val id = v.getOrdinal()
-    val bookName = v.getName()
-    val chapter = v.getChapter()
-    val verseNum = v.getVerse()
-    val chapterTitle = ""
-    val paraTitle = ""
-    val references: MutableList<VerseReference> = ArrayList()
-    var content = ""
+data class VerseContent(val v: Verse,
+                        val id: Int = v.getOrdinal(),
+                        val bookName: String = v.getName(),
+                        val chapter: Int = v.getChapter(),
+                        val verseNum: Int = v.getVerse(),
+                        val chapterTitle: String = "",
+                        val paraTitle: String = "",
+                        val references: MutableList<VerseReference> = ArrayList(),
+                        val content: String = "") {
 
+    // Gson is used mostly for serializing the verses
     public val json: String
         get() = Gson().toJson(this)
 
-    public fun toJson(): String {
-        // Lazy load Gson - not likely that we'll call this method multiple times, so
-        // don't have to worry about a penalty there.
-        return Gson().toJson(this)
-    }
-
-    public fun appendContent(content: String) {
-        this.content += content
-    }
+    public fun appendContent(content: String): VerseContent =
+            this.copy(this.v, content = this.content + content)
 }