From fa2e15ed594bff460bc2defaedc825ba5bdddbf6 Mon Sep 17 00:00:00 2001
From: Jon Parise <jon@pinterest.com>
Date: Fri, 23 Aug 2019 10:53:06 -0700
Subject: [PATCH] Only import the necessary set of types (#235)

We were previously importing the java.util.{Date,List,Map,Set} types
unconditionally. We now detect which types are needed based on walking
the schema and only emitting imports for the types that are actually
used.
---
 Examples/Java/Sources/Board.java               |  1 -
 Examples/Java/Sources/Image.java               |  4 ----
 Examples/Java/Sources/Model.java               |  4 ----
 Examples/Java/Sources/Pin.java                 |  1 -
 Examples/Java/Sources/User.java                |  2 --
 Examples/Java/Sources/VariableSubtitution.java |  4 ----
 Sources/Core/JavaModelRenderer.swift           | 16 +++++++++++-----
 7 files changed, 11 insertions(+), 21 deletions(-)

diff --git a/Examples/Java/Sources/Board.java b/Examples/Java/Sources/Board.java
index e5e23c4a..b9dfb6cf 100644
--- a/Examples/Java/Sources/Board.java
+++ b/Examples/Java/Sources/Board.java
@@ -20,7 +20,6 @@
 import com.google.gson.stream.JsonWriter;
 import java.io.IOException;
 import java.util.Date;
-import java.util.List;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
diff --git a/Examples/Java/Sources/Image.java b/Examples/Java/Sources/Image.java
index 767e00b9..d8c691cf 100644
--- a/Examples/Java/Sources/Image.java
+++ b/Examples/Java/Sources/Image.java
@@ -19,11 +19,7 @@
 import com.google.gson.stream.JsonToken;
 import com.google.gson.stream.JsonWriter;
 import java.io.IOException;
-import java.util.Date;
-import java.util.List;
-import java.util.Map;
 import java.util.Objects;
-import java.util.Set;
 
 public class Image {
 
diff --git a/Examples/Java/Sources/Model.java b/Examples/Java/Sources/Model.java
index f25e0231..a25034b3 100644
--- a/Examples/Java/Sources/Model.java
+++ b/Examples/Java/Sources/Model.java
@@ -19,11 +19,7 @@
 import com.google.gson.stream.JsonToken;
 import com.google.gson.stream.JsonWriter;
 import java.io.IOException;
-import java.util.Date;
-import java.util.List;
-import java.util.Map;
 import java.util.Objects;
-import java.util.Set;
 
 public class Model {
 
diff --git a/Examples/Java/Sources/Pin.java b/Examples/Java/Sources/Pin.java
index 4ed74776..5f773c4e 100644
--- a/Examples/Java/Sources/Pin.java
+++ b/Examples/Java/Sources/Pin.java
@@ -23,7 +23,6 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
-import java.util.Set;
 
 interface PinAttributionObjectsMatcher<R> {
     R match(@Nullable Board value0);
diff --git a/Examples/Java/Sources/User.java b/Examples/Java/Sources/User.java
index 677912d4..c8c04f22 100644
--- a/Examples/Java/Sources/User.java
+++ b/Examples/Java/Sources/User.java
@@ -20,10 +20,8 @@
 import com.google.gson.stream.JsonWriter;
 import java.io.IOException;
 import java.util.Date;
-import java.util.List;
 import java.util.Map;
 import java.util.Objects;
-import java.util.Set;
 
 public class User {
 
diff --git a/Examples/Java/Sources/VariableSubtitution.java b/Examples/Java/Sources/VariableSubtitution.java
index 756ec291..f5cbb69b 100644
--- a/Examples/Java/Sources/VariableSubtitution.java
+++ b/Examples/Java/Sources/VariableSubtitution.java
@@ -19,11 +19,7 @@
 import com.google.gson.stream.JsonToken;
 import com.google.gson.stream.JsonWriter;
 import java.io.IOException;
-import java.util.Date;
-import java.util.List;
-import java.util.Map;
 import java.util.Objects;
-import java.util.Set;
 
 public class VariableSubtitution {
 
diff --git a/Sources/Core/JavaModelRenderer.swift b/Sources/Core/JavaModelRenderer.swift
index 1c9133b4..65746c33 100644
--- a/Sources/Core/JavaModelRenderer.swift
+++ b/Sources/Core/JavaModelRenderer.swift
@@ -389,6 +389,16 @@ public struct JavaModelRenderer: JavaFileRenderer {
             fatalError("java_nullability_annotation_type must be either android-support or androidx. Invalid type provided: " + params[.javaNullabilityAnnotationType]!)
         }
 
+        let propertyTypeImports = properties.compactMap { (_, prop) -> String? in
+            switch prop.schema {
+            case .array: return "java.util.List"
+            case .map: return "java.util.Map"
+            case .set: return "java.util.Set"
+            case .string(format: .some(.dateTime)): return "java.util.Date"
+            default: return nil
+            }
+        }
+
         let imports = [
             JavaIR.Root.imports(names: Set([
                 "com.google.gson.Gson",
@@ -400,14 +410,10 @@ public struct JavaModelRenderer: JavaFileRenderer {
                 "com.google.gson.stream.JsonToken",
                 "com.google.gson.stream.JsonWriter",
                 "java.io.IOException",
-                "java.util.Date",
-                "java.util.Map",
-                "java.util.Set",
-                "java.util.List",
                 "java.util.Objects",
                 nullabilityAnnotationType.package + ".NonNull",
                 nullabilityAnnotationType.package + ".Nullable",
-            ] + (self.decorations.imports ?? []))),
+            ] + propertyTypeImports + (self.decorations.imports ?? []))),
         ]
 
         let enumProps = properties.flatMap { (param, prop) -> [JavaIR.Enum] in