Fix #4991: add/update JsonNode.xxxValue() for non-number scalars

Author: cowtowncoder

release-notes/VERSION

@@ -100,6 +100,8 @@ Versions: 3.x (for earlier see VERSION-2.x)
 #4956: Rename `JsonNode.isContainerNode()` as `isContainerNode()`
 #4958: Extend, improve set of number value accessors for `JsonNode`
   (`JsonNode.intValue()` etc) [JSTEP-3]
+#4991: Extend, improve set of non-number scalar value accessors for `JsonNode`
+  (`JsonNode.booleanValue()` etc) [JSTEP-3]
 #4992: Rename `JsonNodeFactory.textNode()` as `JsonNodeFactory.stringNode()` [JSTEP-3]
 - Remove `MappingJsonFactory`
 - Add context parameter for `TypeSerializer` contextualization (`forProperty()`)

src/main/java/tools/jackson/databind/JsonNode.java

@@ -612,12 +612,39 @@ public String asText(String defaultValue) {
      * Method to use for accessing JSON boolean values (value
      * literals 'true' and 'false').
      * For other types, always returns false.
+     * 
+     * Method that will try to access value of this node as a Java {@code boolean}
+     * which works if (and only if) node contains JSON boolean value: if not,
+     * a {@link JsonNodeException} will be thrown.
+     *<p>
+     * NOTE: for more lenient conversions, use {@link #asBoolean()}
+     *
+     * @return {@code boolean} value this node represents (if JSON boolean)
      *
-     * @return Boolean value this node contains, if any; false for
-     *   non-boolean nodes.
+     * @throws JsonNodeException if node value is not a JSON boolean value
      */
     public abstract boolean booleanValue();
 
+    /**
+     * Method similar to {@link #booleanValue()}, but that will return specified
+     * {@code defaultValue} if this node does not contain a JSON boolean.
+     *
+     * @param defaultValue Value to return if this node does not contain a JSON boolean.
+     *
+     * @return Java {@code boolean} value this node represents (if JSON boolean);
+     *   {@code defaultValue} otherwise
+     */
+    public abstract boolean booleanValue(boolean defaultValue);
+
+    /**
+     * Method similar to {@link #booleanValue()}, but that will return
+     * {@code Optional.empty()} if this node does not contain a JSON boolean.
+     *
+     * @return {@code Optional<Boolean>} value (if node represents JSON boolean);
+     *   {@code Optional.empty()} otherwise
+     */
+    public abstract Optional<Boolean> booleanValueOpt();
+
     /**
      * Method that will try to convert value of this node to a Java <b>boolean</b>.
      * JSON booleans map naturally; integer numbers other than 0 map to true, and

src/main/java/tools/jackson/databind/node/BaseJsonNode.java

@@ -198,7 +198,19 @@ public byte[] binaryValue() {
 
     @Override
     public boolean booleanValue() {
-        return false;
+        return _reportCoercionFail("booleanValue()", Boolean.TYPE, "value type not boolean");
+    }
+
+    @Override
+    public boolean booleanValue(boolean defaultValue) {
+        // Overridden by BooleanNode, for other types return default
+        return defaultValue;
+    }
+
+    @Override
+    public Optional<Boolean> booleanValueOpt() {
+        // Overridden by BooleanNode, for other types return default
+        return Optional.empty();
     }
 
     @Override

src/main/java/tools/jackson/databind/node/BooleanNode.java

@@ -1,5 +1,7 @@
 package tools.jackson.databind.node;
 
+import java.util.Optional;
+
 import tools.jackson.core.*;
 import tools.jackson.databind.SerializationContext;
 
@@ -18,6 +20,9 @@ public class BooleanNode
     public final static BooleanNode TRUE = new BooleanNode(true);
     public final static BooleanNode FALSE = new BooleanNode(false);
 
+    private final static Optional<Boolean> OPT_FALSE = Optional.of(false);
+    private final static Optional<Boolean> OPT_TRUE = Optional.of(true);
+    
     private final boolean _value;
 
     /*
@@ -61,14 +66,25 @@ protected String _valueDesc() {
     @Override
     public BooleanNode deepCopy() { return this; }
 
+    /*
+    /**********************************************************************
+    /* Overridden JsonNode methods, scalar access
+    /**********************************************************************
+     */
+
     @Override
     public boolean booleanValue() {
         return _value;
     }
 
     @Override
-    public String asString() {
-        return _value ? "true" : "false";
+    public boolean booleanValue(boolean defaultValue) {
+        return _value;
+    }
+
+    @Override
+    public Optional<Boolean> booleanValueOpt() {
+        return _value ? OPT_TRUE : OPT_FALSE;
     }
 
     @Override
@@ -94,6 +110,17 @@ public double asDouble(double defaultValue) {
         return _value ? 1.0 : 0.0;
     }
 
+    @Override
+    public String asString() {
+        return _value ? "true" : "false";
+    }
+
+    /*
+    /**********************************************************************
+    /* Overridden JsonNode methods, other
+    /**********************************************************************
+     */
+
     @Override
     public final void serialize(JsonGenerator g, SerializationContext provider)
             throws JacksonException {

src/main/java/tools/jackson/databind/node/IntNode.java

@@ -150,6 +150,12 @@ public boolean asBoolean(boolean defaultValue) {
         return _value != 0;
     }
 
+    /*
+    /**********************************************************************
+    /* Overridden JsonNode methods, other
+    /**********************************************************************
+     */
+    
     @Override
     public final void serialize(JsonGenerator g, SerializationContext provider)
         throws JacksonException

src/test/java/tools/jackson/databind/node/NullNodeTest.java

@@ -45,7 +45,6 @@ public void testBasicsWithNullNode() throws Exception
         assertFalse(n.canConvertToExactIntegral());
 
         // fallback accessors
-        assertFalse(n.booleanValue());
 
         // may be odd but...
         assertEquals("null", n.asString());