Update writer handling (#119)

* Update writer call

* Add helper class which holds the instances of each writer

src/main/kotlin/net/theevilreaper/dartpoet/DartFile.kt

@@ -3,15 +3,14 @@ package net.theevilreaper.dartpoet
 import net.theevilreaper.dartpoet.annotation.AnnotationSpec
 import net.theevilreaper.dartpoet.clazz.ClassSpec
 import net.theevilreaper.dartpoet.code.CodeWriter
+import net.theevilreaper.dartpoet.code.WriterHelper
 import net.theevilreaper.dartpoet.code.buildCodeString
-import net.theevilreaper.dartpoet.code.writer.DartFileWriter
 import net.theevilreaper.dartpoet.directive.DartDirective
 import net.theevilreaper.dartpoet.directive.ExportDirective
 import net.theevilreaper.dartpoet.directive.LibraryDirective
 import net.theevilreaper.dartpoet.directive.PartDirective
 import net.theevilreaper.dartpoet.directive.RelativeDirective
 import net.theevilreaper.dartpoet.extension.ExtensionSpec
-import net.theevilreaper.dartpoet.function.FunctionSpec
 import net.theevilreaper.dartpoet.util.*
 import net.theevilreaper.dartpoet.property.consts.ConstantPropertySpec
 import net.theevilreaper.dartpoet.util.DART_FILE_ENDING
@@ -58,23 +57,11 @@ class DartFile internal constructor(
     }
 
     internal fun write(codeWriter: CodeWriter) {
-        DartFileWriter().write(this, codeWriter)
+        WriterHelper.fileWriter.write(this, codeWriter)
     }
 
     override fun toString() = buildCodeString { write(this) }
 
-    internal val callEmit: (Any, CodeWriter) -> Unit = { o: Any, c: CodeWriter ->
-        emitInternal(o, c)
-    }
-
-    private fun emitInternal(o: Any, c: CodeWriter) {
-        when (o::class) {
-            FunctionSpec::class -> {
-                callEmit(o, c)
-            }
-        }
-    }
-
     /**
      * Writes the content from a [DartFile] to the given [Appendable].
      * @param out the [Appendable] where the content should be written

src/main/kotlin/net/theevilreaper/dartpoet/annotation/AnnotationSpec.kt

@@ -1,7 +1,6 @@
 package net.theevilreaper.dartpoet.annotation
 
 import net.theevilreaper.dartpoet.code.*
-import net.theevilreaper.dartpoet.code.writer.AnnotationWriter
 import net.theevilreaper.dartpoet.type.ClassName
 import net.theevilreaper.dartpoet.type.TypeName
 import net.theevilreaper.dartpoet.type.asClassName
@@ -41,7 +40,7 @@ class AnnotationSpec internal constructor(
         codeWriter: CodeWriter,
         inline: Boolean = true,
     ) {
-        AnnotationWriter().emit(this, codeWriter, inline = inline)
+        WriterHelper.annotationWriter.emit(this, codeWriter, inline = inline)
     }
 
     /**

src/main/kotlin/net/theevilreaper/dartpoet/clazz/ClassSpec.kt

@@ -6,6 +6,7 @@ import net.theevilreaper.dartpoet.DartModifier.WITH
 import net.theevilreaper.dartpoet.InheritKeyword
 import net.theevilreaper.dartpoet.annotation.AnnotationSpec
 import net.theevilreaper.dartpoet.code.CodeWriter
+import net.theevilreaper.dartpoet.code.WriterHelper
 import net.theevilreaper.dartpoet.code.buildCodeString
 import net.theevilreaper.dartpoet.code.writer.ClassWriter
 import net.theevilreaper.dartpoet.enum.EnumPropertySpec
@@ -75,7 +76,7 @@ class ClassSpec internal constructor(
      * @param codeWriter the [CodeWriter] instance to apply the data
      */
     internal fun write(codeWriter: CodeWriter) {
-        ClassWriter().write(this, codeWriter)
+        WriterHelper.classWriter.write(this, codeWriter)
     }
 
     /**

src/main/kotlin/net/theevilreaper/dartpoet/code/WriterHelper.kt

@@ -0,0 +1,35 @@
+package net.theevilreaper.dartpoet.code
+
+import net.theevilreaper.dartpoet.code.writer.*
+import org.jetbrains.annotations.ApiStatus.Internal
+import org.jetbrains.annotations.ApiStatus.NonExtendable
+
+/**
+ * A helper class that holds references to writer implementations.
+ * Maintaining a single instance of each writer improves runtime performance
+ * by avoiding the overhead of creating new instances for each write operation.
+ *
+ * Since writer classes do not store any state, creating new instances is unnecessary.
+ *
+ * **Note**: Update this class only when adding or removing writer implementations.
+ *
+ * @since 1.0.0
+ * author theEvilReaper
+ */
+@Internal
+@NonExtendable
+internal object WriterHelper {
+
+    internal val annotationWriter by lazy { AnnotationWriter() }
+    internal val classWriter by lazy { ClassWriter() }
+    internal val constantPropertyWriter by lazy { ConstantPropertyWriter() }
+    internal val constructorWriter by lazy { ConstructorWriter() }
+    internal val fileWriter by lazy { DartFileWriter() }
+    internal val enumPropertyWriter by lazy { EnumPropertyWriter() }
+    internal val extensionWriter by lazy { ExtensionWriter() }
+    internal val factoryWriter by lazy { FactoryWriter() }
+    internal val functionWriter by lazy { FunctionWriter() }
+    internal val parameterWriter by lazy { ParameterWriter() }
+    internal val propertyWriter by lazy { PropertyWriter() }
+    internal val typeDefWriter by lazy { TypeDefWriter() }
+}

src/main/kotlin/net/theevilreaper/dartpoet/constructor/ConstructorSpec.kt

@@ -1,6 +1,7 @@
 package net.theevilreaper.dartpoet.constructor
 
 import net.theevilreaper.dartpoet.code.CodeWriter
+import net.theevilreaper.dartpoet.code.WriterHelper
 import net.theevilreaper.dartpoet.code.buildCodeString
 import net.theevilreaper.dartpoet.code.writer.ConstructorWriter
 import net.theevilreaper.dartpoet.util.toImmutableList
@@ -37,7 +38,7 @@ class ConstructorSpec internal constructor(
      * @param codeWriter the instance to a [CodeWriter] to append the data
      */
     internal fun write(codeWriter: CodeWriter) {
-        ConstructorWriter().write(this, codeWriter)
+        WriterHelper.constructorWriter.write(this, codeWriter)
     }
 
     /**

src/main/kotlin/net/theevilreaper/dartpoet/constructor/factory/FactorySpec.kt

@@ -3,6 +3,7 @@ package net.theevilreaper.dartpoet.constructor.factory
 import net.theevilreaper.dartpoet.annotation.AnnotationSpec
 import net.theevilreaper.dartpoet.code.CodeBlock
 import net.theevilreaper.dartpoet.code.CodeWriter
+import net.theevilreaper.dartpoet.code.WriterHelper
 import net.theevilreaper.dartpoet.code.buildCodeString
 import net.theevilreaper.dartpoet.code.writer.FactoryWriter
 import net.theevilreaper.dartpoet.constructor.ConstructorBase
@@ -54,7 +55,7 @@ class FactorySpec(
      * @see FactoryWriter
      */
     internal fun write(codeWriter: CodeWriter) {
-        FactoryWriter().write(this, codeWriter)
+        WriterHelper.factoryWriter.write(this, codeWriter)
     }
 
     /**

src/main/kotlin/net/theevilreaper/dartpoet/enum/EnumPropertySpec.kt

@@ -1,6 +1,7 @@
 package net.theevilreaper.dartpoet.enum
 
 import net.theevilreaper.dartpoet.code.CodeWriter
+import net.theevilreaper.dartpoet.code.WriterHelper
 import net.theevilreaper.dartpoet.code.buildCodeString
 import net.theevilreaper.dartpoet.code.writer.EnumPropertyWriter
 import net.theevilreaper.dartpoet.util.toImmutableList
@@ -31,7 +32,7 @@ class EnumPropertySpec internal constructor(
 
 
     internal fun write(codeWriter: CodeWriter) {
-        EnumPropertyWriter().write(this, codeWriter)
+        WriterHelper.enumPropertyWriter.write(this, codeWriter)
     }
 
     /**

src/main/kotlin/net/theevilreaper/dartpoet/extension/ExtensionSpec.kt

@@ -2,6 +2,7 @@ package net.theevilreaper.dartpoet.extension
 
 import net.theevilreaper.dartpoet.code.CodeBlock
 import net.theevilreaper.dartpoet.code.CodeWriter
+import net.theevilreaper.dartpoet.code.WriterHelper
 import net.theevilreaper.dartpoet.code.buildCodeString
 import net.theevilreaper.dartpoet.code.writer.ExtensionWriter
 import net.theevilreaper.dartpoet.function.FunctionSpec
@@ -68,7 +69,7 @@ class ExtensionSpec internal constructor(
      * @param codeWriter the writer instance to apply the data as code
      */
     internal fun write(codeWriter: CodeWriter) {
-        ExtensionWriter().write(this, codeWriter)
+        WriterHelper.extensionWriter.write(this, codeWriter)
     }
 
     /**

src/main/kotlin/net/theevilreaper/dartpoet/function/FunctionSpec.kt

@@ -4,6 +4,7 @@ import net.theevilreaper.dartpoet.DartModifier
 import net.theevilreaper.dartpoet.annotation.AnnotationSpec
 import net.theevilreaper.dartpoet.code.CodeBlock
 import net.theevilreaper.dartpoet.code.CodeWriter
+import net.theevilreaper.dartpoet.code.WriterHelper
 import net.theevilreaper.dartpoet.code.writer.FunctionWriter
 import net.theevilreaper.dartpoet.code.buildCodeString
 import net.theevilreaper.dartpoet.parameter.ParameterSpec
@@ -73,7 +74,7 @@ class FunctionSpec internal constructor(
      * @param codeWriter the writer instance
      */
     internal fun write(codeWriter: CodeWriter) {
-        FunctionWriter().write(this, codeWriter)
+        WriterHelper.functionWriter.write(this, codeWriter)
     }
 
     /**

src/main/kotlin/net/theevilreaper/dartpoet/function/typedef/TypeDefSpec.kt

@@ -1,9 +1,9 @@
 package net.theevilreaper.dartpoet.function.typedef
 
 import net.theevilreaper.dartpoet.code.CodeWriter
+import net.theevilreaper.dartpoet.code.WriterHelper
 import net.theevilreaper.dartpoet.code.buildCodeString
 import net.theevilreaper.dartpoet.code.writer.FunctionWriter
-import net.theevilreaper.dartpoet.code.writer.TypeDefWriter
 import net.theevilreaper.dartpoet.type.ClassName
 import net.theevilreaper.dartpoet.type.TypeName
 import net.theevilreaper.dartpoet.type.asTypeName
@@ -50,7 +50,7 @@ class TypeDefSpec(
      * @param codeWriter the writer instance
      */
     internal fun write(codeWriter: CodeWriter) {
-        TypeDefWriter().write(this, codeWriter)
+        WriterHelper.typeDefWriter.write(this, codeWriter)
     }
 
     /**

src/main/kotlin/net/theevilreaper/dartpoet/parameter/ParameterSpec.kt

@@ -2,6 +2,7 @@ package net.theevilreaper.dartpoet.parameter
 
 import net.theevilreaper.dartpoet.DartModifier
 import net.theevilreaper.dartpoet.code.CodeWriter
+import net.theevilreaper.dartpoet.code.WriterHelper
 import net.theevilreaper.dartpoet.code.buildCodeString
 import net.theevilreaper.dartpoet.code.writer.ParameterWriter
 import net.theevilreaper.dartpoet.type.ClassName
@@ -51,7 +52,7 @@ class ParameterSpec internal constructor(
      * @param codeWriter the [CodeWriter] to which the parameter should be written
      */
     internal fun write(codeWriter: CodeWriter) {
-        ParameterWriter().write(this, codeWriter)
+        WriterHelper.parameterWriter.write(this, codeWriter)
     }
 
     /**

src/main/kotlin/net/theevilreaper/dartpoet/property/PropertySpec.kt

@@ -3,6 +3,7 @@ package net.theevilreaper.dartpoet.property
 import net.theevilreaper.dartpoet.DartModifier
 import net.theevilreaper.dartpoet.annotation.AnnotationSpec
 import net.theevilreaper.dartpoet.code.CodeWriter
+import net.theevilreaper.dartpoet.code.WriterHelper
 import net.theevilreaper.dartpoet.code.writer.PropertyWriter
 import net.theevilreaper.dartpoet.code.buildCodeString
 import net.theevilreaper.dartpoet.type.ClassName
@@ -60,7 +61,7 @@ class PropertySpec internal constructor(
      * @param codeWriter the [CodeWriter] to apply the content from the spec
      */
     internal fun write(codeWriter: CodeWriter) {
-        PropertyWriter().write(this, codeWriter)
+        WriterHelper.propertyWriter.write(this, codeWriter)
     }
 
     /**

src/main/kotlin/net/theevilreaper/dartpoet/property/consts/ConstantPropertySpec.kt

@@ -2,6 +2,7 @@ package net.theevilreaper.dartpoet.property.consts
 
 import net.theevilreaper.dartpoet.DartModifier
 import net.theevilreaper.dartpoet.code.CodeWriter
+import net.theevilreaper.dartpoet.code.WriterHelper
 import net.theevilreaper.dartpoet.code.buildCodeString
 import net.theevilreaper.dartpoet.code.writer.ConstantPropertyWriter
 import net.theevilreaper.dartpoet.property.PropertySpec
@@ -44,7 +45,7 @@ class ConstantPropertySpec(
      * @param codeWriter the [CodeWriter] to apply the content from the spec
      */
     internal fun write(codeWriter: CodeWriter) {
-        ConstantPropertyWriter().write(this, codeWriter)
+        WriterHelper.constantPropertyWriter.write(this, codeWriter)
     }
 
     /**