Use whisker for java

Summary:
Whisker is a replacement for mustache and is largely backward compatible. It brings several quality of life improvements like... error checking.

You can read more about the details [in this post](https://fb.workplace.com/groups/498666380550247/permalink/2051389461944590/).

This diff moves `t_mstch_java_generator` to use whisker instead of mstch.

This requires some changes to the templates to work around the bugs in mstch that have been previously worked around.

#buildall

Reviewed By: iahs

Differential Revision: D67874968

fbshipit-source-id: 6267cd0ed3c04360241fb3f9b45e6f90b3278142

thrift/compiler/generate/t_mstch_java_generator.cc

@@ -159,6 +159,17 @@ class t_mstch_java_generator : public t_mstch_generator {
  public:
   using t_mstch_generator::t_mstch_generator;
 
+  std::optional<whisker_options> use_whisker() const override {
+    whisker_options opts;
+    opts.allowed_undefined_variables = {
+        "type:typedef_type", // in UnionWrite.mustache
+        "struct:isUnion?", // in WriteResponseType.mustache
+        "struct:asBean?", // in DefaultValue.mustache
+        "field:hasAdapter?", // in BoxedType.mustache
+    };
+    return opts;
+  }
+
   std::string template_prefix() const override { return "java"; }
 
   void generate_program() override;

thrift/compiler/generate/templates/java/ReactiveAsyncWrapper.mustache

@@ -18,7 +18,7 @@
 {{> AutoGenerated}}
 
 package {{service:javaPackage}};
-{{#service:disableReactive?}}// Generation of this class is disabled using (java.swift.disable_reactive){{/service:disableReactive?}}{{^service:disableReactive?}}
+
 import java.util.*;
 
 public class {{service:javaCapitalName}}ReactiveAsyncWrapper {{#service:extends}} extends {{service:javaPackage}}.{{service:javaCapitalName}}ReactiveAsyncWrapper{{/service:extends}}
@@ -95,4 +95,3 @@ public class {{service:javaCapitalName}}ReactiveAsyncWrapper {{#service:extends}
   {{/last?}}
   {{/service:interactions}}
 }
-{{/service:disableReactive?}}

thrift/compiler/generate/templates/java/ReactiveBlockingWrapper.mustache

@@ -18,7 +18,7 @@
 {{> AutoGenerated}}
 
 package {{service:javaPackage}};
-{{#service:disableReactive?}}// Generation of this class is disabled using (java.swift.disable_reactive){{/service:disableReactive?}}{{^service:disableReactive?}}
+
 import java.util.*;
 
 public class {{service:javaCapitalName}}ReactiveBlockingWrapper {{#service:extends}} extends {{service:javaPackage}}.{{service:javaCapitalName}}ReactiveBlockingWrapper{{/service:extends}}
@@ -94,4 +94,3 @@ public class {{service:javaCapitalName}}ReactiveBlockingWrapper {{#service:exten
   {{/last?}}
   {{/service:interactions}}
 }
-{{/service:disableReactive?}}

thrift/compiler/generate/templates/java/struct/StructBuilder.mustache

@@ -27,7 +27,7 @@ public static class Builder {
     {{#field:isSensitive?}}
     @org.apache.thrift.annotations.Sensitive
     {{/field:isSensitive?}}
-    {{> ThriftFieldAnnotation}}{{#field:javaAnnotation?}} @{{field:javaAnnotation}}{{/field:javaAnnotation?}}
+    {{> ThriftFieldAnnotation}}
     {{#field:hasWrapper?}}
     public Builder {{> SetterName}}({{field:wrapperType}} {{field:javaName}}) {
         this.{{field:javaName}} = {{field:javaName}};

thrift/compiler/test/fixtures/adapter/out/java/gen-java/test/fixtures/adapter/A.java

@@ -28,7 +28,7 @@ public A(
     }
 
 
-    
+
     public static Builder builder() {
       return new Builder();
     }
@@ -50,7 +50,7 @@ public A build() {
             return result;
         }
     }
-        
+
     public static final Map<String, Integer> NAMES_TO_IDS = new HashMap<>();
     public static final Map<String, Integer> THRIFT_NAMES_TO_IDS = new HashMap<>();
     public static final Map<Integer, TField> FIELD_METADATA = new HashMap<>();
@@ -65,7 +65,7 @@ public String toString() {
         ToStringHelper helper = toStringHelper(this);
         return helper.toString();
     }
-    
+
     @java.lang.Override
     public boolean equals(java.lang.Object o) {
         if (this == o) {
@@ -80,13 +80,13 @@ public boolean equals(java.lang.Object o) {
         return
             true;
     }
-    
+
     @java.lang.Override
     public int hashCode() {
         return Arrays.deepHashCode(new java.lang.Object[] {
         });
     }
-    
+
 
     public static com.facebook.thrift.payload.Reader<A> asReader() {
       return A::read0;
@@ -109,13 +109,13 @@ public static A read0(TProtocol oprot) throws TException {
       oprot.readStructEnd();
       return builder.build();
     }
-    
+
     public void write0(TProtocol oprot) throws TException {
       oprot.writeStructBegin(STRUCT_DESC);
       oprot.writeFieldStop();
       oprot.writeStructEnd();
     }
-    
+
     private static class _ALazy {
         private static final A _DEFAULT = new A.Builder().build();
     }

thrift/compiler/test/fixtures/adapter/out/java/gen-java/test/fixtures/adapter/AdaptTemplatedNestedTestStruct.java

@@ -33,7 +33,7 @@ public AdaptTemplatedNestedTestStruct(
     protected AdaptTemplatedNestedTestStruct() {
       this.adaptedStruct = null;
     }
-    
+
     public static Builder builder() {
       return new Builder();
     }
@@ -45,8 +45,7 @@ public static Builder builder(AdaptTemplatedNestedTestStruct other) {
     public static class Builder {
         private test.fixtures.adapter.AdaptTemplatedTestStruct adaptedStruct = null;
 
-        @com.facebook.swift.codec.ThriftField(value=1, name="adaptedStruct", requiredness=Requiredness.NONE)
-        public Builder setAdaptedStruct(test.fixtures.adapter.AdaptTemplatedTestStruct adaptedStruct) {
+        @com.facebook.swift.codec.ThriftField(value=1, name="adaptedStruct", requiredness=Requiredness.NONE)    public Builder setAdaptedStruct(test.fixtures.adapter.AdaptTemplatedTestStruct adaptedStruct) {
             this.adaptedStruct = adaptedStruct;
             return this;
         }
@@ -66,7 +65,7 @@ public AdaptTemplatedNestedTestStruct build() {
             return result;
         }
     }
-        
+
     public static final Map<String, Integer> NAMES_TO_IDS = new HashMap<>();
     public static final Map<String, Integer> THRIFT_NAMES_TO_IDS = new HashMap<>();
     public static final Map<Integer, TField> FIELD_METADATA = new HashMap<>();
@@ -86,14 +85,14 @@ public AdaptTemplatedNestedTestStruct build() {
     @Nullable
     @com.facebook.swift.codec.ThriftField(value=1, name="adaptedStruct", requiredness=Requiredness.NONE)
     public test.fixtures.adapter.AdaptTemplatedTestStruct getAdaptedStruct() { return adaptedStruct; }
-    
+
     @java.lang.Override
     public String toString() {
         ToStringHelper helper = toStringHelper(this);
         helper.add("adaptedStruct", adaptedStruct);
         return helper.toString();
     }
-    
+
     @java.lang.Override
     public boolean equals(java.lang.Object o) {
         if (this == o) {
@@ -109,14 +108,14 @@ public boolean equals(java.lang.Object o) {
             Objects.equals(adaptedStruct, other.adaptedStruct) &&
             true;
     }
-    
+
     @java.lang.Override
     public int hashCode() {
         return Arrays.deepHashCode(new java.lang.Object[] {
             adaptedStruct
         });
     }
-    
+
 
     public static com.facebook.thrift.payload.Reader<AdaptTemplatedNestedTestStruct> asReader() {
       return AdaptTemplatedNestedTestStruct::read0;
@@ -147,7 +146,7 @@ public static AdaptTemplatedNestedTestStruct read0(TProtocol oprot) throws TExce
       oprot.readStructEnd();
       return builder.build();
     }
-    
+
     public void write0(TProtocol oprot) throws TException {
       oprot.writeStructBegin(STRUCT_DESC);
       if (adaptedStruct != null) {
@@ -158,7 +157,7 @@ public void write0(TProtocol oprot) throws TException {
       oprot.writeFieldStop();
       oprot.writeStructEnd();
     }
-    
+
     private static class _AdaptTemplatedNestedTestStructLazy {
         private static final AdaptTemplatedNestedTestStruct _DEFAULT = new AdaptTemplatedNestedTestStruct.Builder().build();
     }