Add an LRU Cache for stored items

src/main/java/it/smartphonecombo/uecapabilityparser/cli/Clikt.kt

@@ -229,6 +229,10 @@ object Server : CliktCommand(name = "server", help = "Starts ue capability parse
             option("--reparse", help = HelpMessage.REPARSE, metavar = "Strategy")
                 .choice("off", "auto", "force")
                 .default("off")
+        val cache by
+            option("--cache", metavar = "Items", help = HelpMessage.LIBRARY_CACHE)
+                .int()
+                .default(1000)
     }
 
     private const val DEFAULT_PORT = 0
@@ -267,6 +271,7 @@ object Server : CliktCommand(name = "server", help = "Starts ue capability parse
             Config["store"] = it.path
             Config["compression"] = it.compression.toString()
             Config["reparse"] = it.reparse
+            Config["cache"] = it.cache.toString()
         }
 
         // Start server
@@ -293,6 +298,13 @@ object Server : CliktCommand(name = "server", help = "Starts ue capability parse
         if (Config.getOrDefault("reparse", "off") != "off")
             features += "reparse ${Config["reparse"]}"
 
+        features +=
+            when (val items = Config["cache"]?.toIntOrNull()?.takeIf { it >= 0 }) {
+                0 -> "cache disabled"
+                null -> "cache unlimited"
+                else -> "cache $items items"
+            }
+
         val featuresString =
             if (features.isNotEmpty()) {
                 features.joinToString(" + ", " with ")

src/main/java/it/smartphonecombo/uecapabilityparser/cli/HelpMessage.kt

@@ -54,4 +54,6 @@ object HelpMessage {
     const val NEW_CSV_FORMAT = "Use new CSV format for LTE CA"
     const val CUSTOM_CSS = "Inject custom css in Web UI"
     const val CUSTOM_JS = "Inject custom js in Web UI"
+    const val LIBRARY_CACHE =
+        "Number of items to cache, each items occupies ~0.15MB of RAM. 0 = disabled, -1 = unlimited."
 }

src/main/java/it/smartphonecombo/uecapabilityparser/extension/Collections.kt

@@ -57,3 +57,9 @@ internal fun BwMap.merge(other: BwMap) {
         this[key] = this[key]?.plus(value) ?: value
     }
 }
+
+internal fun <T> List<T>.trimToSize() {
+    if (this is ArrayList) {
+        this.trimToSize()
+    }
+}

src/main/java/it/smartphonecombo/uecapabilityparser/model/index/LibraryIndex.kt

@@ -4,8 +4,12 @@ import it.smartphonecombo.uecapabilityparser.extension.custom
 import it.smartphonecombo.uecapabilityparser.extension.decodeFromInputSource
 import it.smartphonecombo.uecapabilityparser.extension.nameWithoutAnyExtension
 import it.smartphonecombo.uecapabilityparser.extension.toInputSource
+import it.smartphonecombo.uecapabilityparser.io.IOUtils
 import it.smartphonecombo.uecapabilityparser.io.IOUtils.createDirectories
 import it.smartphonecombo.uecapabilityparser.io.IOUtils.echoSafe
+import it.smartphonecombo.uecapabilityparser.model.Capabilities
+import it.smartphonecombo.uecapabilityparser.util.LruCache
+import it.smartphonecombo.uecapabilityparser.util.optimize
 import java.io.File
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.Transient
@@ -14,9 +18,11 @@ import kotlinx.serialization.json.Json
 @Serializable
 data class LibraryIndex(
     private val items: MutableList<IndexLine>,
-    private val multiItems: MutableList<MultiIndexLine> = mutableListOf()
+    private val multiItems: MutableList<MultiIndexLine> = mutableListOf(),
+    @Transient private val outputCacheSize: Int? = 0
 ) {
     @Transient private val lock = Any()
+    @Transient private val outputCache = LruCache<String, Capabilities>(outputCacheSize)
 
     fun addLine(line: IndexLine): Boolean {
         synchronized(lock) {
@@ -42,13 +48,24 @@ data class LibraryIndex(
         return items.find { item -> item.inputs.any { it == id } }
     }
 
-    fun findByOutput(id: String): IndexLine? = find(id)
-
     /** return a list of all single-capability indexes */
     fun getAll() = items.toList()
 
+    fun getOutput(id: String, libraryPath: String): Capabilities? {
+        val cached = outputCache[id]
+        if (cached != null) return cached
+
+        val indexLine = find(id) ?: return null
+        val compressed = indexLine.compressed
+        val filePath = "$libraryPath/output/$id.json"
+        val text = IOUtils.getInputSource(filePath, compressed) ?: return null
+        val res = Json.custom().decodeFromInputSource<Capabilities>(text)
+        if (outputCache.put(id, res)) res.optimize()
+        return res
+    }
+
     companion object {
-        fun buildIndex(path: String): LibraryIndex {
+        fun buildIndex(path: String, outputCacheSize: Int?): LibraryIndex {
             val outputDir = "$path/output"
             val inputDir = "$path/input"
             val multiDir = "$path/multi"
@@ -108,7 +125,7 @@ data class LibraryIndex(
             items.sortBy { it.timestamp }
             multiItems.sortBy { it.timestamp }
 
-            return LibraryIndex(items, multiItems)
+            return LibraryIndex(items, multiItems, outputCacheSize)
         }
     }
 }

src/main/java/it/smartphonecombo/uecapabilityparser/server/JavalinApp.kt

@@ -103,16 +103,18 @@ class JavalinApp {
     init {
         val store = Config["store"]
         val compression = Config["compression"] == "true"
+        val maxOutputCache = Config.getOrDefault("cache", "0").toInt().takeIf { it >= 0 }
         var index: LibraryIndex =
-            store?.let { LibraryIndex.buildIndex(it) } ?: LibraryIndex(mutableListOf())
+            store?.let { LibraryIndex.buildIndex(it, maxOutputCache) }
+                ?: LibraryIndex(mutableListOf())
         val idRegex = "[a-f0-9-]{36}(?:-[0-9]+)?".toRegex()
 
         val reparseStrategy = Config.getOrDefault("reparse", "off")
         if (store != null && reparseStrategy != "off") {
             CoroutineScope(Dispatchers.IO).launch {
                 reparseLibrary(reparseStrategy, store, index, compression)
                 // Rebuild index
-                index = LibraryIndex.buildIndex(store)
+                index = LibraryIndex.buildIndex(store, maxOutputCache)
             }
         }
 
@@ -210,15 +212,9 @@ class JavalinApp {
                         return@apiBuilderGet ctx.badRequest()
                     }
 
-                    val indexLine = index.findByOutput(id) ?: return@apiBuilderGet ctx.notFound()
-                    val compressed = indexLine.compressed
-                    val filePath = "$store/output/$id.json"
-
                     try {
-                        val text =
-                            IOUtils.getInputSource(filePath, compressed)
-                                ?: return@apiBuilderGet ctx.notFound()
-                        val capabilities = Json.custom().decodeFromInputSource<Capabilities>(text)
+                        val capabilities =
+                            index.getOutput(id, store) ?: return@apiBuilderGet ctx.notFound()
                         ctx.json(capabilities)
                     } catch (ex: Exception) {
                         ctx.internalError()
@@ -235,15 +231,7 @@ class JavalinApp {
                     val capabilitiesList = mutableListWithCapacity<Capabilities>(indexLineIds.size)
                     try {
                         for (indexId in indexLineIds) {
-                            val indexLine = index.find(indexId) ?: continue
-                            val compressed = indexLine.compressed
-                            val outputId = indexLine.id
-                            val filePath = "$store/output/$outputId.json"
-                            val text =
-                                IOUtils.getInputSource(filePath, compressed)
-                                    ?: return@apiBuilderGet ctx.notFound()
-                            val capabilities =
-                                Json.custom().decodeFromInputSource<Capabilities>(text)
+                            val capabilities = index.getOutput(indexId, store) ?: continue
                             capabilitiesList.add(capabilities)
                         }
                     } catch (ex: Exception) {

src/main/java/it/smartphonecombo/uecapabilityparser/util/Intern.kt

@@ -0,0 +1,38 @@
+package it.smartphonecombo.uecapabilityparser.util
+
+import it.smartphonecombo.uecapabilityparser.model.EmptyMimo
+import it.smartphonecombo.uecapabilityparser.model.Mimo
+import it.smartphonecombo.uecapabilityparser.model.bandwidth.Bandwidth
+import it.smartphonecombo.uecapabilityparser.model.bandwidth.EmptyBandwidth
+import it.smartphonecombo.uecapabilityparser.model.modulation.EmptyModulation
+import it.smartphonecombo.uecapabilityparser.model.modulation.Modulation
+
+open class InternMap<T>(maxCapacity: Int) {
+    private val internalMap: LinkedHashMap<T, T> =
+        object : LinkedHashMap<T, T>(minOf(16, maxCapacity), 0.75f) {
+            override fun removeEldestEntry(eldest: Map.Entry<T, T>): Boolean {
+                return size > maxCapacity
+            }
+        }
+
+    private fun put(value: T): T {
+        internalMap[value] = value
+        return value
+    }
+
+    fun intern(value: T): T = internalMap[value] ?: put(value)
+}
+
+object MimoInternMap : InternMap<Mimo>(100)
+
+object ModulationInternMap : InternMap<Modulation>(100)
+
+object BandwidthInternMap : InternMap<Bandwidth>(100)
+
+internal fun Mimo.intern(): Mimo = if (this == EmptyMimo) this else MimoInternMap.intern(this)
+
+internal fun Modulation.intern() =
+    if (this == EmptyModulation) this else ModulationInternMap.intern(this)
+
+internal fun Bandwidth.intern() =
+    if (this == EmptyBandwidth) this else BandwidthInternMap.intern(this)

src/main/java/it/smartphonecombo/uecapabilityparser/util/LruCache.kt

@@ -0,0 +1,31 @@
+package it.smartphonecombo.uecapabilityparser.util
+
+class LruCache<K, V>(private val maxCapacity: Int? = null) {
+    private val internalMap: LinkedHashMap<K, V>
+    private val lock = Any()
+
+    init {
+        if (maxCapacity == null) {
+            internalMap = LinkedHashMap()
+        } else {
+            internalMap =
+                object : LinkedHashMap<K, V>(minOf(16, maxCapacity + 1), 0.75f, true) {
+                    override fun removeEldestEntry(eldest: Map.Entry<K, V>): Boolean {
+                        return size > maxCapacity
+                    }
+                }
+        }
+    }
+
+    operator fun get(key: K): V? = internalMap[key]
+
+    operator fun set(key: K, value: V) = put(key, value)
+
+    fun put(key: K, value: V, skipIfFull: Boolean = false): Boolean {
+        if (maxCapacity == 0 || skipIfFull && full()) return false
+        synchronized(lock) { internalMap[key] = value }
+        return true
+    }
+
+    private fun full(): Boolean = maxCapacity == internalMap.size
+}

src/main/java/it/smartphonecombo/uecapabilityparser/util/Optimization.kt

@@ -0,0 +1,42 @@
+package it.smartphonecombo.uecapabilityparser.util
+
+import it.smartphonecombo.uecapabilityparser.extension.trimToSize
+import it.smartphonecombo.uecapabilityparser.model.Capabilities
+import it.smartphonecombo.uecapabilityparser.model.band.IBandDetails
+import it.smartphonecombo.uecapabilityparser.model.combo.ICombo
+import it.smartphonecombo.uecapabilityparser.model.component.ComponentNr
+import it.smartphonecombo.uecapabilityparser.model.component.IComponent
+
+internal fun Capabilities.optimize() {
+    lteBands.forEach { it.optimize() }
+    nrBands.forEach { it.optimize() }
+    lteCombos.forEach { it.optimize() }
+    nrCombos.forEach { it.optimize() }
+    nrDcCombos.forEach { it.optimize() }
+    enDcCombos.forEach { it.optimize() }
+}
+
+internal fun IBandDetails.optimize() {
+    mimoDL = mimoDL.intern()
+    mimoUL = mimoUL.intern()
+    modDL = modDL.intern()
+    modUL = modUL.intern()
+}
+
+internal fun ICombo.optimize() {
+    masterComponents.trimToSize()
+    masterComponents.forEach { it.optimize() }
+    secondaryComponents.trimToSize()
+    secondaryComponents.forEach { it.optimize() }
+}
+
+internal fun IComponent.optimize() {
+    mimoDL = mimoDL.intern()
+    mimoUL = mimoUL.intern()
+    modDL = modDL.intern()
+    modUL = modUL.intern()
+    if (this is ComponentNr) {
+        maxBandwidthDl = maxBandwidthDl.intern()
+        maxBandwidthUl = maxBandwidthUl.intern()
+    }
+}

src/test/java/it/smartphonecombo/uecapabilityparser/server/ServerModeMultiStoreTest.kt

@@ -205,6 +205,7 @@ internal class ServerModeMultiStoreTest {
     @Test
     fun getMultiOutput() {
         Config["store"] = "$resourcesPath/oracleForMultiStore"
+        Config["cache"] = "-1"
         getTest(
             "${endpointStore}getMultiOutput?id=${storedMultiId}",
             "$resourcesPath/oracleForMultiStore/multiParseOutput.json",

src/test/java/it/smartphonecombo/uecapabilityparser/server/ServerModeStoreTest.kt

@@ -51,12 +51,14 @@ internal class ServerModeStoreTest {
     @Test
     fun emptyList() {
         Config["store"] = tmpStorePath
+        Config["cache"] = "0"
         getTest(endpointStore + "list", "$resourcesPath/oracleForStore/emptyList.json")
     }
 
     @Test
     fun storeElement() {
         Config["store"] = tmpStorePath
+        Config["cache"] = "-1"
         val oracle = "$resourcesPath/oracleForStore/output/$storedId.json"
         val input0 = "$resourcesPath/oracleForStore/input/$storedId-0"
         val input1 = "$resourcesPath/oracleForStore/input/$storedId-1"
@@ -121,6 +123,7 @@ internal class ServerModeStoreTest {
 
     @Test
     fun getOutput() {
+        Config["cache"] = "1000"
         Config["store"] = "$resourcesPath/oracleForStore"
         getTest(
             "${endpointStore}getOutput?id=$storedId",