diff --git a/gson/src/main/java/org/baeldung/gson/primitives/models/BooleanExample.java b/gson/src/main/java/org/baeldung/gson/primitives/models/BooleanExample.java new file mode 100644 index 0000000000..1fe87650de --- /dev/null +++ b/gson/src/main/java/org/baeldung/gson/primitives/models/BooleanExample.java @@ -0,0 +1,9 @@ +package org.baeldung.gson.primitives.models; + +public class BooleanExample { + public boolean value; + + public String toString() { + return "{boolean: " + value + "}"; + } +} diff --git a/gson/src/main/java/org/baeldung/gson/primitives/models/ByteExample.java b/gson/src/main/java/org/baeldung/gson/primitives/models/ByteExample.java new file mode 100644 index 0000000000..2e1c68ee51 --- /dev/null +++ b/gson/src/main/java/org/baeldung/gson/primitives/models/ByteExample.java @@ -0,0 +1,9 @@ +package org.baeldung.gson.primitives.models; + +public class ByteExample { + public byte value = (byte) 1; + + public String toString() { + return "{byte: " + value + "}"; + } +} diff --git a/gson/src/main/java/org/baeldung/gson/primitives/models/CharExample.java b/gson/src/main/java/org/baeldung/gson/primitives/models/CharExample.java new file mode 100644 index 0000000000..ccac913f23 --- /dev/null +++ b/gson/src/main/java/org/baeldung/gson/primitives/models/CharExample.java @@ -0,0 +1,9 @@ +package org.baeldung.gson.primitives.models; + +public class CharExample { + public char value; + + public String toString() { + return "{char: " + value + "}"; + } +} diff --git a/gson/src/main/java/org/baeldung/gson/primitives/models/DoubleExample.java b/gson/src/main/java/org/baeldung/gson/primitives/models/DoubleExample.java new file mode 100644 index 0000000000..5022b6a11e --- /dev/null +++ b/gson/src/main/java/org/baeldung/gson/primitives/models/DoubleExample.java @@ -0,0 +1,9 @@ +package org.baeldung.gson.primitives.models; + +public class DoubleExample { + public double value; + + public String toString() { + return "{float: " + value + "}"; + } +} diff --git a/gson/src/main/java/org/baeldung/gson/primitives/models/FloatExample.java b/gson/src/main/java/org/baeldung/gson/primitives/models/FloatExample.java new file mode 100644 index 0000000000..00a97f68fc --- /dev/null +++ b/gson/src/main/java/org/baeldung/gson/primitives/models/FloatExample.java @@ -0,0 +1,9 @@ +package org.baeldung.gson.primitives.models; + +public class FloatExample { + public float value; + + public String toString() { + return "{float: " + value + "}"; + } +} diff --git a/gson/src/main/java/org/baeldung/gson/primitives/models/InfinityValuesExample.java b/gson/src/main/java/org/baeldung/gson/primitives/models/InfinityValuesExample.java new file mode 100644 index 0000000000..163b0a3d95 --- /dev/null +++ b/gson/src/main/java/org/baeldung/gson/primitives/models/InfinityValuesExample.java @@ -0,0 +1,6 @@ +package org.baeldung.gson.primitives.models; + +public class InfinityValuesExample { + public float negativeInfinity; + public float positiveInfinity; +} diff --git a/gson/src/main/java/org/baeldung/gson/primitives/models/LongExample.java b/gson/src/main/java/org/baeldung/gson/primitives/models/LongExample.java new file mode 100644 index 0000000000..e709650789 --- /dev/null +++ b/gson/src/main/java/org/baeldung/gson/primitives/models/LongExample.java @@ -0,0 +1,9 @@ +package org.baeldung.gson.primitives.models; + +public class LongExample { + public long value = 1; + + public String toString() { + return "{byte: " + value + "}"; + } +} diff --git a/gson/src/main/java/org/baeldung/gson/primitives/models/PrimitiveBundle.java b/gson/src/main/java/org/baeldung/gson/primitives/models/PrimitiveBundle.java new file mode 100644 index 0000000000..ad7309a2f7 --- /dev/null +++ b/gson/src/main/java/org/baeldung/gson/primitives/models/PrimitiveBundle.java @@ -0,0 +1,19 @@ +package org.baeldung.gson.primitives.models; + +public class PrimitiveBundle { + public byte byteValue; + public short shortValue; + public int intValue; + public long longValue; + public float floatValue; + public double doubleValue; + public boolean booleanValue; + public char charValue; + + public String toString() { + return "{" + "byte: " + byteValue + ", " + "short: " + shortValue + ", " + + "int: " + intValue + ", " + "long: " + longValue + ", " + + "float: " + floatValue + ", " + "double: " + doubleValue + ", " + + "boolean: " + booleanValue + ", " + "char: " + charValue + "}"; + } +} diff --git a/gson/src/main/java/org/baeldung/gson/primitives/models/PrimitiveBundleInitialized.java b/gson/src/main/java/org/baeldung/gson/primitives/models/PrimitiveBundleInitialized.java new file mode 100644 index 0000000000..2780f7fd18 --- /dev/null +++ b/gson/src/main/java/org/baeldung/gson/primitives/models/PrimitiveBundleInitialized.java @@ -0,0 +1,18 @@ +package org.baeldung.gson.primitives.models; + +public class PrimitiveBundleInitialized { + // @formatter:off + public byte byteValue = (byte) 1; + public short shortValue = (short) 1; + public int intValue = 1; + public long longValue = 1L; + public float floatValue = 1.0f; + public double doubleValue = 1; + // @formatter:on + + public String toString() { + return "{" + "byte: " + byteValue + ", " + "short: " + shortValue + ", " + + "int: " + intValue + ", " + "long: " + longValue + ", " + + "float: " + floatValue + ", " + "double: " + doubleValue + "}"; + } +} diff --git a/gson/src/test/java/org/baeldung/gson/primitives/PrimitiveValuesUnitTest.java b/gson/src/test/java/org/baeldung/gson/primitives/PrimitiveValuesUnitTest.java new file mode 100644 index 0000000000..7d249bc55c --- /dev/null +++ b/gson/src/test/java/org/baeldung/gson/primitives/PrimitiveValuesUnitTest.java @@ -0,0 +1,248 @@ +package org.baeldung.gson.primitives; + +import com.google.gson.*; +import org.baeldung.gson.primitives.models.*; +import org.junit.Test; + +import java.lang.reflect.Type; + +import static junit.framework.TestCase.*; + +public class PrimitiveValuesUnitTest { + @Test public void whenSerializingToJSON_thenShouldCreateJSON() { + PrimitiveBundle primitiveBundle = new PrimitiveBundle(); + + // @formatter:off + primitiveBundle.byteValue = (byte) 0x00001111; + primitiveBundle.shortValue = (short) 3; + primitiveBundle.intValue = 3; + primitiveBundle.longValue = 3; + primitiveBundle.floatValue = 3.5f; + primitiveBundle.doubleValue = 3.5; + primitiveBundle.booleanValue = true; + primitiveBundle.charValue = 'a'; + // @formatter:on + + Gson gson = new Gson(); + + String expected = "{\"byteValue\":17,\"shortValue\":3,\"intValue\":3," + + "\"longValue\":3,\"floatValue\":3.5" + ",\"doubleValue\":3.5" + + ",\"booleanValue\":true,\"charValue\":\"a\"}"; + + assertEquals(expected, gson.toJson(primitiveBundle)); + } + + @Test(expected = IllegalArgumentException.class) public void + whenSerializingInfinity_thenShouldRaiseAnException() { + InfinityValuesExample model = new InfinityValuesExample(); + model.negativeInfinity = Float.NEGATIVE_INFINITY; + model.positiveInfinity = Float.POSITIVE_INFINITY; + + Gson gson = new Gson(); + + gson.toJson(model); + } + + @Test(expected = IllegalArgumentException.class) public void + whenSerializingNaN_thenShouldRaiseAnException() { + FloatExample model = new FloatExample(); + model.value = Float.NaN; + + Gson gson = new Gson(); + gson.toJson(model); + } + + @Test public void whenDeserializingFromJSON_thenShouldParseTheValueInTheString() { + String json = "{\"byteValue\": 17, \"shortValue\": 3, \"intValue\": 3, " + + "\"longValue\": 3, \"floatValue\": 3.5" + ", \"doubleValue\": 3.5" + + ", \"booleanValue\": true, \"charValue\": \"a\"}"; + + Gson gson = new Gson(); + PrimitiveBundle model = gson.fromJson(json, PrimitiveBundle.class); + + // @formatter:off + assertEquals(17, model.byteValue); + assertEquals(3, model.shortValue); + assertEquals(3, model.intValue); + assertEquals(3, model.longValue); + assertEquals(3.5, model.floatValue, 0.0001); + assertEquals(3.5, model.doubleValue, 0.0001); + assertTrue( model.booleanValue); + assertEquals('a', model.charValue); + // @formatter:on + } + + @Test public void whenDeserializingHighPrecissionNumberIntoFloat_thenShouldPerformRounding() { + String json = "{\"value\": 12.123425589123456}"; + Gson gson = new Gson(); + FloatExample model = gson.fromJson(json, FloatExample.class); + assertEquals(12.123426f, model.value, 0.000001); + } + + @Test public void whenDeserializingHighPrecissiongNumberIntoDouble_thenShouldPerformRounding() { + String json = "{\"value\": 12.123425589123556}"; + Gson gson = new Gson(); + DoubleExample model = gson.fromJson(json, DoubleExample.class); + assertEquals(12.123425589124f, model.value, 0.000001); + } + + + @Test public void whenDeserializingValueThatOverflows_thenShouldOverflowSilently() { + Gson gson = new Gson(); + String json = "{\"value\": \"300\"}"; + ByteExample model = gson.fromJson(json, ByteExample.class); + + assertEquals(44, model.value); + } + + @Test public void whenDeserializingRealIntoByte_thenShouldRaiseAnException() { + Gson gson = new Gson(); + String json = "{\"value\": 2.3}"; + try { + gson.fromJson(json, ByteExample.class); + } catch (Exception ex) { + assertTrue(ex instanceof JsonSyntaxException); + assertTrue(ex.getCause() instanceof NumberFormatException); + return; + } + + fail(); + } + + @Test public void whenDeserializingRealIntoLong_thenShouldRaiseAnException() { + Gson gson = new Gson(); + String json = "{\"value\": 2.3}"; + try { + gson.fromJson(json, LongExample.class); + } catch (Exception ex) { + assertTrue(ex instanceof JsonSyntaxException); + assertTrue(ex.getCause() instanceof NumberFormatException); + return; + } + + fail(); + } + + @Test public void whenDeserializingRealWhoseDecimalPartIs0_thenShouldParseItCorrectly() { + Gson gson = new Gson(); + String json = "{\"value\": 2.0}"; + LongExample model = gson.fromJson(json, LongExample.class); + assertEquals(2, model.value); + } + + @Test public void whenDeserializingUnicodeChar_thenShouldParseItCorrectly() { + Gson gson = new Gson(); + String json = "{\"value\": \"\\u00AE\"}"; + CharExample model = gson.fromJson(json, CharExample.class); + + assertEquals('\u00AE', model.value); + } + + @Test public void whenDeserializingNullValues_thenShouldIgnoreThoseFields() { + Gson gson = new Gson(); + // @formatter:off + String json = "{\"byteValue\": null, \"shortValue\": null, " + + "\"intValue\": null, " + "\"longValue\": null, \"floatValue\": null" + + ", \"doubleValue\": null}"; + // @formatter:on + PrimitiveBundleInitialized model = gson.fromJson(json, + PrimitiveBundleInitialized.class); + + assertEquals(1, model.byteValue); + assertEquals(1, model.shortValue); + assertEquals(1, model.intValue); + assertEquals(1, model.longValue); + assertEquals(1, model.floatValue, 0.0001); + assertEquals(1, model.doubleValue, 0.0001); + } + + @Test(expected = JsonSyntaxException.class) public void + whenDeserializingTheEmptyString_thenShouldRaiseAnException() { + Gson gson = new Gson(); + // @formatter:off + String json = "{\"byteValue\": \"\", \"shortValue\": \"\", " + + "\"intValue\": \"\", " + "\"longValue\": \"\", \"floatValue\": \"\"" + + ", \"doubleValue\": \"\"" + ", \"booleanValue\": \"\"}"; + // @formatter:on + gson.fromJson(json, PrimitiveBundleInitialized.class); + } + + @Test public void whenDeserializingTheEmptyStringIntoChar_thenShouldHaveTheEmtpyChar() { + Gson gson = new Gson(); + // @formatter:off + String json = "{\"charValue\": \"\"}"; + // @formatter:on + CharExample model = gson.fromJson(json, CharExample.class); + + assertEquals(Character.MIN_VALUE, model.value); + } + + @Test public void whenDeserializingValidValueAppearingInAString_thenShouldParseTheValue() { + Gson gson = new Gson(); + // @formatter:off + String json = "{\"byteValue\": \"15\", \"shortValue\": \"15\", " + + "\"intValue\": \"15\", " + "\"longValue\": \"15\", \"floatValue\": \"15.0\"" + + ", \"doubleValue\": \"15.0\"}"; + // @formatter:on + PrimitiveBundleInitialized model = gson.fromJson(json, + PrimitiveBundleInitialized.class); + + assertEquals(15, model.byteValue); + assertEquals(15, model.shortValue); + assertEquals(15, model.intValue); + assertEquals(15, model.longValue); + assertEquals(15, model.floatValue, 0.0001); + assertEquals(15, model.doubleValue, 0.0001); + } + + @Test public void whenDeserializingABooleanFrom0Or1Integer_thenShouldRaiseAnException() { + String json = "{\"value\": 1}"; + Gson gson = new Gson(); + + try { + gson.fromJson(json, BooleanExample.class); + } catch (Exception ex) { + assertTrue(ex instanceof JsonSyntaxException); + assertTrue(ex.getCause() instanceof IllegalStateException); + return; + } + + fail(); + } + + @Test public void whenDeserializingWithCustomDeserializerABooleanFrom0Or1Integer_thenShouldWork() { + String json = "{\"value\": 1}"; + GsonBuilder builder = new GsonBuilder(); + builder.registerTypeAdapter(BooleanExample.class, + new BooleanAs2ValueIntegerDeserializer()); + + Gson gson = builder.create(); + + BooleanExample model = gson.fromJson(json, BooleanExample.class); + + assertTrue(model.value); + } + + // @formatter:off + static class BooleanAs2ValueIntegerDeserializer implements JsonDeserializer { + @Override public BooleanExample deserialize( + JsonElement jsonElement, + Type type, + JsonDeserializationContext jsonDeserializationContext) throws JsonParseException { + + BooleanExample model = new BooleanExample(); + int value = jsonElement.getAsJsonObject().getAsJsonPrimitive("value").getAsInt(); + if (value == 0) { + model.value = false; + } else if (value == 1) { + model.value = true; + } else { + throw new JsonParseException("Unexpected value. Trying to deserialize " + + "a boolean from an integer different than 0 and 1."); + } + + return model; + } + } + // @formatter:on +}