[FE] Read Java static field initializer lazily (KTIJ-23043)

compiler/fir/java/src/org/jetbrains/kotlin/fir/java/FirJavaFacade.kt

@@ -25,7 +25,6 @@ import org.jetbrains.kotlin.fir.declarations.impl.FirResolvedDeclarationStatusIm
 import org.jetbrains.kotlin.fir.declarations.utils.effectiveVisibility
 import org.jetbrains.kotlin.fir.declarations.utils.modality
 import org.jetbrains.kotlin.fir.expressions.FirConstExpression
-import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.classId
 import org.jetbrains.kotlin.fir.java.declarations.*
 import org.jetbrains.kotlin.fir.java.enhancement.FirSignatureEnhancement
@@ -539,7 +538,11 @@ abstract class FirJavaFacade(
                 isVar = !javaField.isFinal
                 isStatic = javaField.isStatic
                 annotationBuilder = { javaField.convertAnnotationsToFir(session, javaTypeParameterStack) }
-                initializer = convertJavaInitializerToFir(javaField.initializerValue)
+
+                lazyInitializer = lazy {
+                    // NB: null should be converted to null
+                    javaField.initializerValue?.createConstantIfAny(session)
+                }
 
                 if (!javaField.isStatic) {
                     dispatchReceiverType = dispatchReceiver
@@ -552,11 +555,6 @@ abstract class FirJavaFacade(
         }
     }
 
-    private fun convertJavaInitializerToFir(value: Any?): FirExpression? {
-        // NB: null should be converted to null
-        return value?.createConstantIfAny(session)
-    }
-
     private fun convertJavaMethodToFir(
         containingClass: JavaClass,
         javaMethod: JavaMethod,

compiler/fir/java/src/org/jetbrains/kotlin/fir/java/declarations/FirJavaField.kt

@@ -44,7 +44,7 @@ class FirJavaField @FirImplementationDetail constructor(
     override val isVar: Boolean,
     annotationBuilder: () -> List<FirAnnotation>,
     override val typeParameters: MutableList<FirTypeParameterRef>,
-    override var initializer: FirExpression?,
+    private var lazyInitializer: Lazy<FirExpression?>,
     override val dispatchReceiverType: ConeSimpleKotlinType?,
     override val attributes: FirDeclarationAttributes,
 ) : FirField() {
@@ -61,6 +61,9 @@ class FirJavaField @FirImplementationDetail constructor(
 
     override val annotations: List<FirAnnotation> by lazy { annotationBuilder() }
 
+    override val initializer: FirExpression?
+        get() = lazyInitializer.value
+
     override val deprecationsProvider: DeprecationsProvider by lazy {
         annotations.getDeprecationsProviderFromAnnotations(fromJava = true, moduleData.session.firCachesFactory)
     }
@@ -87,7 +90,7 @@ class FirJavaField @FirImplementationDetail constructor(
 
     override fun <D> transformOtherChildren(transformer: FirTransformer<D>, data: D): FirField {
         transformAnnotations(transformer, data)
-        initializer = initializer?.transformSingle(transformer, data)
+        replaceInitializer(initializer?.transformSingle(transformer, data))
         return this
     }
 
@@ -127,7 +130,7 @@ class FirJavaField @FirImplementationDetail constructor(
     }
 
     override fun replaceInitializer(newInitializer: FirExpression?) {
-        initializer = newInitializer
+        lazyInitializer = lazyOf(newInitializer)
     }
 
     override fun <D> transformTypeParameters(transformer: FirTransformer<D>, data: D): FirField {
@@ -169,6 +172,7 @@ internal class FirJavaFieldBuilder : FirFieldBuilder() {
     var isStatic: Boolean by Delegates.notNull()
     var isFromSource: Boolean by Delegates.notNull()
     lateinit var annotationBuilder: () -> List<FirAnnotation>
+    var lazyInitializer: Lazy<FirExpression?>? = null
 
     override var resolvePhase: FirResolvePhase = FirResolvePhase.ANALYZED_DEPENDENCIES
 
@@ -186,7 +190,7 @@ internal class FirJavaFieldBuilder : FirFieldBuilder() {
             isVar,
             annotationBuilder,
             typeParameters,
-            initializer,
+            lazyInitializer ?: lazyOf(initializer),
             dispatchReceiverType,
             attributes,
         )