Supporting other primitives as backing types for enums

jsonschema2pojo-core/src/main/java/org/jsonschema2pojo/rules/EnumRule.java

@@ -17,6 +17,7 @@
 package org.jsonschema2pojo.rules;
 
 import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.sun.codemodel.ClassType;
 import com.sun.codemodel.JAnnotationUse;
 import com.sun.codemodel.JBlock;
@@ -27,6 +28,7 @@
 import com.sun.codemodel.JDefinedClass;
 import com.sun.codemodel.JEnumConstant;
 import com.sun.codemodel.JExpr;
+import com.sun.codemodel.JExpression;
 import com.sun.codemodel.JFieldVar;
 import com.sun.codemodel.JForEach;
 import com.sun.codemodel.JInvocation;
@@ -72,7 +74,7 @@ public class EnumRule implements Rule<JClassContainer, JType> {
     private static final String VALUE_FIELD_NAME = "value";
 
     private final RuleFactory ruleFactory;
-
+    
     protected EnumRule(RuleFactory ruleFactory) {
         this.ruleFactory = ruleFactory;
     }
@@ -118,11 +120,28 @@ public JType apply(String nodeName, JsonNode node, JClassContainer container, Sc
             addInterfaces(_enum, node.get("javaInterfaces"));
         }
         addGeneratedAnnotation(_enum);
-
-        JFieldVar valueField = addValueField(_enum);
-        addToString(_enum, valueField);
-        addEnumConstants(node.path("enum"), _enum, node.path("javaEnumNames"));
-        addFactoryMethod(_enum);
+
+        // copy our node; remove the javaType as it will throw off the TypeRule for our case
+        ObjectNode typeNode = (ObjectNode)node.deepCopy();
+        typeNode.remove("javaType");
+
+        // If type is specified on the enum, get a type rule for it.  Otherwise, we're a string.
+        // (This is different from the default of Object, which is why we don't do this for every case.)
+        JType backingType = node.has("type") ? 
+                ruleFactory.getTypeRule().apply(nodeName, typeNode, container, schema) :
+                container.owner().ref(String.class);
+
+        JFieldVar valueField = addValueField(_enum, backingType);
+
+        // override toString only if we have a sensible string to return
+        if(isString(backingType)){
+            addToString(_enum, valueField);
+        }
+
+        addValueMethod(_enum, valueField);
+
+        addEnumConstants(node.path("enum"), _enum, node.path("javaEnumNames"), backingType);
+        addFactoryMethod(_enum, backingType);
 
         return _enum;
     }
@@ -157,11 +176,11 @@ private JDefinedClass createEnum(JsonNode node, String nodeName, JClassContainer
         }
     }
 
-    private void addFactoryMethod(JDefinedClass _enum) {
-        JFieldVar quickLookupMap = addQuickLookupMap(_enum);
+    private void addFactoryMethod(JDefinedClass _enum, JType backingType) {
+        JFieldVar quickLookupMap = addQuickLookupMap(_enum, backingType);
 
         JMethod fromValue = _enum.method(JMod.PUBLIC | JMod.STATIC, _enum, "fromValue");
-        JVar valueParam = fromValue.param(String.class, "value");
+        JVar valueParam = fromValue.param(backingType, "value");
 
         JBlock body = fromValue.body();
         JVar constant = body.decl(_enum, "constant");
@@ -170,19 +189,26 @@ private void addFactoryMethod(JDefinedClass _enum) {
         JConditional _if = body._if(constant.eq(JExpr._null()));
 
         JInvocation illegalArgumentException = JExpr._new(_enum.owner().ref(IllegalArgumentException.class));
-        illegalArgumentException.arg(valueParam);
+        JExpression expr = valueParam;
+
+        // if string no need to add ""
+        if(!isString(backingType)){
+            expr = expr.plus(JExpr.lit(""));
+        }
+
+        illegalArgumentException.arg(expr);
         _if._then()._throw(illegalArgumentException);
         _if._else()._return(constant);
 
         ruleFactory.getAnnotator().enumCreatorMethod(fromValue);
     }
 
-    private JFieldVar addQuickLookupMap(JDefinedClass _enum) {
+    private JFieldVar addQuickLookupMap(JDefinedClass _enum, JType backingType) {
 
-        JClass lookupType = _enum.owner().ref(Map.class).narrow(_enum.owner().ref(String.class), _enum);
+        JClass lookupType = _enum.owner().ref(Map.class).narrow(backingType.boxify(), _enum);
         JFieldVar lookupMap = _enum.field(JMod.PRIVATE | JMod.STATIC | JMod.FINAL, lookupType, "CONSTANTS");
 
-        JClass lookupImplType = _enum.owner().ref(HashMap.class).narrow(_enum.owner().ref(String.class), _enum);
+        JClass lookupImplType = _enum.owner().ref(HashMap.class).narrow(backingType.boxify(), _enum);
         lookupMap.init(JExpr._new(lookupImplType));
 
         JForEach forEach = _enum.init().forEach(_enum, "c", JExpr.invoke("values"));
@@ -193,11 +219,11 @@ private JFieldVar addQuickLookupMap(JDefinedClass _enum) {
         return lookupMap;
     }
 
-    private JFieldVar addValueField(JDefinedClass _enum) {
-        JFieldVar valueField = _enum.field(JMod.PRIVATE | JMod.FINAL, String.class, VALUE_FIELD_NAME);
+    private JFieldVar addValueField(JDefinedClass _enum, JType type) {
+        JFieldVar valueField = _enum.field(JMod.PRIVATE | JMod.FINAL, type, VALUE_FIELD_NAME);
 
         JMethod constructor = _enum.constructor(JMod.PRIVATE);
-        JVar valueParam = constructor.param(String.class, VALUE_FIELD_NAME);
+        JVar valueParam = constructor.param(type, VALUE_FIELD_NAME);
         JBlock body = constructor.body();
         body.assign(JExpr._this().ref(valueField), valueParam);
 
@@ -208,13 +234,30 @@ private void addToString(JDefinedClass _enum, JFieldVar valueField) {
         JMethod toString = _enum.method(JMod.PUBLIC, String.class, "toString");
         JBlock body = toString.body();
 
-        body._return(JExpr._this().ref(valueField));
+        JExpression toReturn = JExpr._this().ref(valueField);
+        if(!isString(valueField.type())){
+            toReturn = toReturn.plus(JExpr.lit(""));
+        }
+
+        body._return(toReturn);
 
-        ruleFactory.getAnnotator().enumValueMethod(toString);
         toString.annotate(Override.class);
     }
+
+    private void addValueMethod(JDefinedClass _enum, JFieldVar valueField) {
+        JMethod fromValue = _enum.method(JMod.PUBLIC, valueField.type(), "value");
 
-    private void addEnumConstants(JsonNode node, JDefinedClass _enum, JsonNode customNames) {
+        JBlock body = fromValue.body();
+        body._return(JExpr._this().ref(valueField));
+
+        ruleFactory.getAnnotator().enumValueMethod(fromValue);
+    }
+
+    private boolean isString(JType type){
+        return type.fullName().equals(String.class.getName());
+    }
+
+    private void addEnumConstants(JsonNode node, JDefinedClass _enum, JsonNode customNames, JType type) {
         Collection<String> existingConstantNames = new ArrayList<String>();
         for (int i = 0; i < node.size(); i++) {
             JsonNode value = node.path(i);
@@ -225,7 +268,20 @@ private void addEnumConstants(JsonNode node, JDefinedClass _enum, JsonNode custo
                 existingConstantNames.add(constantName);
 
                 JEnumConstant constant = _enum.enumConstant(constantName);
-                constant.arg(JExpr.lit(value.asText()));
+
+                String typeName = type.unboxify().fullName(); 
+                if(typeName.equals("int")){ // integer
+                    constant.arg(JExpr.lit(value.intValue()));   
+                } else if(typeName.equals("long")){ // integer-as-long
+                    constant.arg(JExpr.lit(value.longValue()));
+                } else if(typeName.equals("double")){ // number
+                    constant.arg(JExpr.lit(value.doubleValue()));
+                } else if(typeName.equals("boolean")){ // boolean
+                    constant.arg(JExpr.lit(value.booleanValue()));    
+                } else { // string, null, array, object?  
+                    // only string should really be valid here... TODO throw error?
+                    constant.arg(JExpr.lit(value.asText()));
+                }
                 ruleFactory.getAnnotator().enumConstant(constant, value.asText());
             }
         }

jsonschema2pojo-core/src/test/java/org/jsonschema2pojo/rules/EnumRuleTest.java

@@ -45,13 +45,15 @@ public class EnumRuleTest {
     private NameHelper nameHelper = mock(NameHelper.class);
     private Annotator annotator = mock(Annotator.class);
     private RuleFactory ruleFactory = mock(RuleFactory.class);
+    private TypeRule typeRule = mock(TypeRule.class);
 
     private EnumRule rule = new EnumRule(ruleFactory);
 
     @Before
     public void wireUpConfig() {
         when(ruleFactory.getNameHelper()).thenReturn(nameHelper);
         when(ruleFactory.getAnnotator()).thenReturn(annotator);
+        when(ruleFactory.getTypeRule()).thenReturn(typeRule);
     }
 
     @Test
@@ -71,6 +73,10 @@ public void applyGeneratesUniqueEnumNamesForMultipleEnumNodesWithSameName() {
         ObjectNode enumNode = objectMapper.createObjectNode();
         enumNode.put("type", "string");
         enumNode.put("enum", arrayNode);
+
+        // We're always a string for the purposes of this test
+        when(typeRule.apply("status", enumNode, jpackage, schema))
+            .thenReturn(jpackage.owner()._ref(String.class));
 
         JType result1 = rule.apply("status", enumNode, jpackage, schema);
         JType result2 = rule.apply("status", enumNode, jpackage, schema);

jsonschema2pojo-integration-tests/src/test/java/org/jsonschema2pojo/integration/EnumIT.java

@@ -25,6 +25,7 @@
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 
+import org.hamcrest.core.IsInstanceOf;
 import org.jsonschema2pojo.integration.util.Jsonschema2PojoRule;
 import org.junit.BeforeClass;
 import org.junit.ClassRule;
@@ -33,6 +34,8 @@
 
 import com.fasterxml.jackson.annotation.JsonCreator;
 import com.fasterxml.jackson.annotation.JsonValue;
+import com.fasterxml.jackson.core.JsonParseException;
+import com.fasterxml.jackson.databind.JsonMappingException;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 
@@ -79,7 +82,7 @@ public void enumClassIncludesCorrectlyNamedConstants() {
     @Test
     public void enumContainsWorkingAnnotatedSerializationMethod() throws NoSuchMethodException {
 
-        Method toString = enumClass.getMethod("toString");
+        Method toString = enumClass.getMethod("value");
 
         assertThat(enumClass.getEnumConstants()[0].toString(), is("one"));
         assertThat(enumClass.getEnumConstants()[1].toString(), is("secondOne"));
@@ -128,7 +131,33 @@ public void enumAtRootCreatesATopLevelType() throws ClassNotFoundException, NoSu
         assertThat(isPublic(rootEnumClass.getModifiers()), is(true));
 
     }
+
+    @Test
+    @SuppressWarnings("unchecked")
+    public void intEnumAtRootCreatesIntBackedEnum() throws ClassNotFoundException, NoSuchMethodException, IllegalAccessException, InvocationTargetException {
+
+        ClassLoader resultsClassLoader = schemaRule.generateAndCompile("/schema/enum/integerEnumAsRoot.json", "com.example");
+
+        Class<Enum> rootEnumClass = (Class<Enum>) resultsClassLoader.loadClass("com.example.enums.IntegerEnumAsRoot");
+
+        assertThat(rootEnumClass.isEnum(), is(true));
+        assertThat(rootEnumClass.getDeclaredMethod("fromValue", Integer.class), is(notNullValue()));
+        assertThat(isPublic(rootEnumClass.getModifiers()), is(true));
+    }
+
+    @Test
+    @SuppressWarnings("unchecked")
+    public void doubleEnumAtRootCreatesIntBackedEnum() throws ClassNotFoundException, NoSuchMethodException, IllegalAccessException, InvocationTargetException {
+
+        ClassLoader resultsClassLoader = schemaRule.generateAndCompile("/schema/enum/doubleEnumAsRoot.json", "com.example");
 
+        Class<Enum> rootEnumClass = (Class<Enum>) resultsClassLoader.loadClass("com.example.enums.DoubleEnumAsRoot");
+
+        assertThat(rootEnumClass.isEnum(), is(true));
+        assertThat(rootEnumClass.getDeclaredMethod("fromValue", Double.class), is(notNullValue()));
+        assertThat(isPublic(rootEnumClass.getModifiers()), is(true));
+    }
+
     @Test
     @SuppressWarnings("unchecked")
     public void enumWithEmptyStringAsValue() throws ClassNotFoundException, NoSuchMethodException, IllegalAccessException, InvocationTargetException {
@@ -226,7 +255,65 @@ public void enumWithCustomJavaNames() throws ClassNotFoundException, NoSuchMetho
         assertThat(jsonTree.get("enum_Property").isTextual(), is(true));
         assertThat(jsonTree.get("enum_Property").asText(), is("3"));
     }
+
+    @Test
+    @SuppressWarnings("unchecked")
+    public void intEnumIsDeserializedCorrectly() throws ClassNotFoundException, NoSuchMethodException, IllegalAccessException, InvocationTargetException, JsonParseException, JsonMappingException, IOException {
+
+        ClassLoader resultsClassLoader = schemaRule.generateAndCompile("/schema/enum/integerEnumToSerialize.json", "com.example");
+
+        // the schema for a valid instance
+        Class<?> typeWithEnumProperty = resultsClassLoader.loadClass("com.example.enums.IntegerEnumToSerialize");
+        Class<Enum> enumClass = (Class<Enum>) resultsClassLoader.loadClass("com.example.enums.IntegerEnumToSerialize$TestEnum");
+
+        // read the instance into the type
+        ObjectMapper objectMapper = new ObjectMapper();
+        Object valueWithEnumProperty = objectMapper.readValue("{\"testEnum\" : 2}", typeWithEnumProperty);
+
+        Method getEnumMethod = typeWithEnumProperty.getDeclaredMethod("getTestEnum");
+        Method getValueMethod = enumClass.getDeclaredMethod("value");
+
+        // call getTestEnum on the value
+        assertThat(getEnumMethod, is(notNullValue()));
+        Object enumObject = getEnumMethod.invoke(valueWithEnumProperty);
+
+        // assert that the object returned is a) a TestEnum, and b) calling .value() on it returns 2
+        // as per the json snippet above
+        assertThat(enumObject, IsInstanceOf.instanceOf(enumClass));
+        assertThat(getValueMethod, is(notNullValue()));
+        assertThat((Integer)getValueMethod.invoke(enumObject), is(2));
+    }
 
+    @Test
+    @SuppressWarnings("unchecked")
+    public void intEnumIsSerializedCorrectly() throws ClassNotFoundException, NoSuchMethodException, IllegalAccessException, InvocationTargetException, JsonParseException, JsonMappingException, IOException, InstantiationException {
+
+        ClassLoader resultsClassLoader = schemaRule.generateAndCompile("/schema/enum/integerEnumToSerialize.json", "com.example");
+
+        // the schema for a valid instance
+        Class<?> typeWithEnumProperty = resultsClassLoader.loadClass("com.example.enums.IntegerEnumToSerialize");
+        Class<Enum> enumClass = (Class<Enum>) resultsClassLoader.loadClass("com.example.enums.IntegerEnumToSerialize$TestEnum");
+
+        // create an instance
+        Object valueWithEnumProperty = typeWithEnumProperty.newInstance();
+        Method enumSetter = typeWithEnumProperty.getMethod("setTestEnum", enumClass);
+
+        // call setTestEnum(TestEnum.ONE)
+        enumSetter.invoke(valueWithEnumProperty, enumClass.getEnumConstants()[0]);
+
+        ObjectMapper objectMapper = new ObjectMapper();
+
+        // write our instance out to json
+        String jsonString = objectMapper.writeValueAsString(valueWithEnumProperty);
+        JsonNode jsonTree = objectMapper.readTree(jsonString);
+
+        assertThat(jsonTree.size(), is(1));
+        assertThat(jsonTree.has("testEnum"), is(true));
+        assertThat(jsonTree.get("testEnum").isIntegralNumber(), is(true));
+        assertThat(jsonTree.get("testEnum").asInt(), is(1));
+    }
+
+
     @Test
     @SuppressWarnings("unchecked")
     public void jacksonCanMarshalEnums() throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException, IOException {

jsonschema2pojo-integration-tests/src/test/resources/schema/enum/doubleEnumAsRoot.json

@@ -0,0 +1,6 @@
+{
+    "javaType" : "com.example.enums.DoubleEnumAsRoot",
+    "type" : "number",
+    "enum" : [1.0, 2.5, 3],
+    "javaEnumNames" : ["One", "TwoAndAHalf", "Three"]
+}

jsonschema2pojo-integration-tests/src/test/resources/schema/enum/integerEnumAsRoot.json

@@ -0,0 +1,6 @@
+{
+    "javaType" : "com.example.enums.IntegerEnumAsRoot",
+    "type" : "integer",
+    "enum" : [1, 2, 3],
+    "javaEnumNames" : ["One", "Two", "Three"]
+}

jsonschema2pojo-integration-tests/src/test/resources/schema/enum/integerEnumToSerialize.json

@@ -0,0 +1,10 @@
+{
+    "javaType" : "com.example.enums.IntegerEnumToSerialize",
+    "properties" : {
+    	"testEnum" : { 
+    		"type" : "integer",
+		    "enum" : [1, 2, 3],
+		    "javaEnumNames" : ["One", "Two", "Three"]
+		}
+    }
+}