#2885 hasFractionalPart method added (#2891)

#2885: Add JsonNode.hasFractionalPart()

Co-authored-by: siavashsoleymani <[email protected]>

Author: siavashsoleymani

src/main/java/com/fasterxml/jackson/databind/JsonNode.java

@@ -316,6 +316,14 @@ public final boolean isNumber() {
      */
     public boolean isInt() { return false; }
 
+    /**
+     * Method that can be used to check whether contained value
+     * has a fractional part or not.
+     *
+     * @return True if the value has fractional part
+     */
+    public boolean hasFractionalPart() { return false; }
+
     /**
      * Method that can be used to check whether contained value
      * is a number represented as Java <code>long</code>.

src/main/java/com/fasterxml/jackson/databind/node/DecimalNode.java

@@ -57,6 +57,11 @@ public class DecimalNode
     @Override
     public boolean isBigDecimal() { return true; }
 
+    @Override
+    public boolean hasFractionalPart() {
+        return !(_value.signum() == 0 || _value.scale() <= 0 || _value.stripTrailingZeros().scale() <= 0);
+    }
+
     @Override public boolean canConvertToInt() {
         return (_value.compareTo(MIN_INTEGER) >= 0) && (_value.compareTo(MAX_INTEGER) <= 0);
     }

src/main/java/com/fasterxml/jackson/databind/node/DoubleNode.java

@@ -52,6 +52,11 @@ public class DoubleNode
     @Override
     public boolean isDouble() { return true; }
 
+    @Override
+    public boolean hasFractionalPart() {
+        return !Double.isNaN(_value) && !Double.isInfinite(_value) && _value % 1 != 0.0;
+    }
+
     @Override public boolean canConvertToInt() {
         return (_value >= Integer.MIN_VALUE && _value <= Integer.MAX_VALUE);
     }

src/main/java/com/fasterxml/jackson/databind/node/FloatNode.java

@@ -1,13 +1,14 @@
 package com.fasterxml.jackson.databind.node;
 
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonToken;
+import com.fasterxml.jackson.core.io.NumberOutput;
+import com.fasterxml.jackson.databind.SerializerProvider;
 import java.io.IOException;
 import java.math.BigDecimal;
 import java.math.BigInteger;
 
-import com.fasterxml.jackson.core.*;
-import com.fasterxml.jackson.core.io.NumberOutput;
-import com.fasterxml.jackson.databind.SerializerProvider;
-
 /**
  * <code>JsonNode</code> implementation for efficiently containing 32-bit
  * `float` values.
@@ -52,6 +53,11 @@ public class FloatNode extends NumericNode
     @Override
     public boolean isFloat() { return true; }
 
+    @Override
+    public boolean hasFractionalPart() {
+        return !Float.isNaN(_value) && !Float.isInfinite(_value) && _value % 1 != 0.0;
+    }
+
     @Override public boolean canConvertToInt() {
         return (_value >= Integer.MIN_VALUE && _value <= Integer.MAX_VALUE);
     }

src/test/java/com/fasterxml/jackson/databind/node/NumberNodesTest.java

@@ -50,6 +50,7 @@ public void testIntViaMapper() throws Exception
         assertType(result, IntNode.class);
         assertFalse(result.isLong());
         assertFalse(result.isFloatingPointNumber());
+        assertFalse(result.hasFractionalPart());
         assertFalse(result.isDouble());
         assertFalse(result.isNull());
         assertFalse(result.isTextual());
@@ -131,6 +132,7 @@ public void testLongViaMapper() throws Exception
         assertType(result, LongNode.class);
         assertFalse(result.isInt());
         assertFalse(result.isFloatingPointNumber());
+        assertFalse(result.hasFractionalPart());
         assertFalse(result.isDouble());
         assertFalse(result.isNull());
         assertFalse(result.isTextual());
@@ -185,6 +187,7 @@ public void testDoubleViaMapper() throws Exception
         assertFalse(result.isNull());
         assertType(result, DoubleNode.class);
         assertTrue(result.isFloatingPointNumber());
+        assertTrue(result.hasFractionalPart());
         assertTrue(result.isDouble());
         assertFalse(result.isInt());
         assertFalse(result.isLong());
@@ -211,7 +214,9 @@ public void testFloat()
         assertEquals(JsonToken.VALUE_NUMBER_FLOAT, n.asToken());
         assertEquals(JsonParser.NumberType.FLOAT, n.numberType());
         assertEquals(0, n.intValue());
-        
+        assertTrue(n.isFloatingPointNumber());
+        assertTrue(n.hasFractionalPart());
+
         // NOTE: conversion to double NOT as simple as with exact numbers like 0.25:
         assertEquals(0.45f, n.floatValue());
         assertEquals("0.45", n.asText());
@@ -281,6 +286,7 @@ public void testDecimalNode() throws Exception
         assertType(result, DecimalNode.class);
         assertFalse(result.isInt());
         assertTrue(result.isFloatingPointNumber());
+        assertTrue(result.hasFractionalPart());
         assertTrue(result.isBigDecimal());
         assertFalse(result.isDouble());
         assertFalse(result.isNull());