Merge pull request #528 from AppDevNext/KotlinFileUtils

Kotlin file utils

Author: hannesa2

MPChartLib/src/main/java/com/github/mikephil/charting/utils/AssetManagerUtils.kt

@@ -0,0 +1,72 @@
+package com.github.mikephil.charting.utils
+
+import android.content.res.AssetManager
+import android.util.Log
+import com.github.mikephil.charting.data.BarEntry
+import com.github.mikephil.charting.data.Entry
+import java.io.BufferedReader
+import java.io.IOException
+import java.io.InputStreamReader
+import java.nio.charset.StandardCharsets
+
+/**
+ * Utilities class for interacting with the assets and the devices storage to load and save DataSet objects from and to .txt files.
+ */
+private const val LOG = "Chart-FileUtils"
+
+/**
+ * Loads an array of Entries from a textfile from the assets folder.
+ *
+ * @param path the name of the file in the assets folder (+ path if needed)
+ */
+fun AssetManager.loadEntriesFromAssets(path: String): MutableList<Entry> {
+    val entries: MutableList<Entry> = ArrayList()
+
+    try {
+        BufferedReader(
+            InputStreamReader(this.open(path), StandardCharsets.UTF_8)
+        ).use { reader ->
+            var line = reader.readLine()
+            while (line != null) {
+                // process line
+                val split: Array<String?> = line.split("#".toRegex()).dropLastWhile { it.isEmpty() }.toTypedArray()
+
+                if (split.size <= 2) {
+                    entries.add(Entry(split[1]!!.toFloat(), split[0]!!.toFloat()))
+                } else {
+                    val vals = FloatArray(split.size - 1)
+
+                    for (i in vals.indices) {
+                        vals[i] = split[i]!!.toFloat()
+                    }
+
+                    entries.add(BarEntry(split[split.size - 1]!!.toInt().toFloat(), vals))
+                }
+                line = reader.readLine()
+            }
+        }
+    } catch (e: IOException) {
+        Log.e(LOG, e.toString())
+    }
+
+    return entries
+}
+
+fun AssetManager.loadBarEntriesFromAssets(path: String): MutableList<BarEntry> {
+    val entries: MutableList<BarEntry> = ArrayList()
+
+    try {
+        BufferedReader(InputStreamReader(this.open(path), StandardCharsets.UTF_8)).use { reader ->
+            var line = reader.readLine()
+            while (line != null) {
+                val split: Array<String?> = line.split("#".toRegex()).dropLastWhile { it.isEmpty() }.toTypedArray()
+                entries.add(BarEntry(split[1]!!.toFloat(), split[0]!!.toFloat()))
+                line = reader.readLine()
+            }
+        }
+    } catch (e: IOException) {
+        Log.e(LOG, e.toString())
+    }
+
+    return entries
+}