/*
* Copyright (C) 2008 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.gson;
import java.math.
BigDecimal;
import java.math.
BigInteger;
import com.google.gson.internal.
$Gson$Preconditions;
import com.google.gson.internal.
LazilyParsedNumber;
/**
* A class representing a Json primitive value. A primitive value
* is either a String, a Java primitive, or a Java primitive
* wrapper type.
*
* @author Inderjeet Singh
* @author Joel Leitch
*/
public final class
JsonPrimitive extends
JsonElement {
private static final
Class<?>[]
PRIMITIVE_TYPES = { int.class, long.class, short.class,
float.class, double.class, byte.class, boolean.class, char.class,
Integer.class,
Long.class,
Short.class,
Float.class,
Double.class,
Byte.class,
Boolean.class,
Character.class };
private
Object value;
/**
* Create a primitive containing a boolean value.
*
* @param bool the value to create the primitive with.
*/
public
JsonPrimitive(
Boolean bool) {
setValue(
bool);
}
/**
* Create a primitive containing a {@link Number}.
*
* @param number the value to create the primitive with.
*/
public
JsonPrimitive(
Number number) {
setValue(
number);
}
/**
* Create a primitive containing a String value.
*
* @param string the value to create the primitive with.
*/
public
JsonPrimitive(
String string) {
setValue(
string);
}
/**
* Create a primitive containing a character. The character is turned into a one character String
* since Json only supports String.
*
* @param c the value to create the primitive with.
*/
public
JsonPrimitive(
Character c) {
setValue(
c);
}
/**
* Create a primitive using the specified Object. It must be an instance of {@link Number}, a
* Java primitive type, or a String.
*
* @param primitive the value to create the primitive with.
*/
JsonPrimitive(
Object primitive) {
setValue(
primitive);
}
/**
* Returns the same value as primitives are immutable.
* @since 2.8.2
*/
@
Override
public
JsonPrimitive deepCopy() {
return this;
}
void
setValue(
Object primitive) {
if (
primitive instanceof
Character) {
// convert characters to strings since in JSON, characters are represented as a single
// character string
char
c = ((
Character)
primitive).
charValue();
this.
value =
String.
valueOf(
c);
} else {
$Gson$Preconditions.
checkArgument(
primitive instanceof
Number
||
isPrimitiveOrString(
primitive));
this.
value =
primitive;
}
}
/**
* Check whether this primitive contains a boolean value.
*
* @return true if this primitive contains a boolean value, false otherwise.
*/
public boolean
isBoolean() {
return
value instanceof
Boolean;
}
/**
* convenience method to get this element as a {@link Boolean}.
*
* @return get this element as a {@link Boolean}.
*/
@
Override
Boolean getAsBooleanWrapper() {
return (
Boolean)
value;
}
/**
* convenience method to get this element as a boolean value.
*
* @return get this element as a primitive boolean value.
*/
@
Override
public boolean
getAsBoolean() {
if (
isBoolean()) {
return
getAsBooleanWrapper().
booleanValue();
} else {
// Check to see if the value as a String is "true" in any case.
return
Boolean.
parseBoolean(
getAsString());
}
}
/**
* Check whether this primitive contains a Number.
*
* @return true if this primitive contains a Number, false otherwise.
*/
public boolean
isNumber() {
return
value instanceof
Number;
}
/**
* convenience method to get this element as a Number.
*
* @return get this element as a Number.
* @throws NumberFormatException if the value contained is not a valid Number.
*/
@
Override
public
Number getAsNumber() {
return
value instanceof
String ? new
LazilyParsedNumber((
String)
value) : (
Number)
value;
}
/**
* Check whether this primitive contains a String value.
*
* @return true if this primitive contains a String value, false otherwise.
*/
public boolean
isString() {
return
value instanceof
String;
}
/**
* convenience method to get this element as a String.
*
* @return get this element as a String.
*/
@
Override
public
String getAsString() {
if (
isNumber()) {
return
getAsNumber().
toString();
} else if (
isBoolean()) {
return
getAsBooleanWrapper().
toString();
} else {
return (
String)
value;
}
}
/**
* convenience method to get this element as a primitive double.
*
* @return get this element as a primitive double.
* @throws NumberFormatException if the value contained is not a valid double.
*/
@
Override
public double
getAsDouble() {
return
isNumber() ?
getAsNumber().
doubleValue() :
Double.
parseDouble(
getAsString());
}
/**
* convenience method to get this element as a {@link BigDecimal}.
*
* @return get this element as a {@link BigDecimal}.
* @throws NumberFormatException if the value contained is not a valid {@link BigDecimal}.
*/
@
Override
public
BigDecimal getAsBigDecimal() {
return
value instanceof
BigDecimal ? (
BigDecimal)
value : new
BigDecimal(
value.
toString());
}
/**
* convenience method to get this element as a {@link BigInteger}.
*
* @return get this element as a {@link BigInteger}.
* @throws NumberFormatException if the value contained is not a valid {@link BigInteger}.
*/
@
Override
public
BigInteger getAsBigInteger() {
return
value instanceof
BigInteger ?
(
BigInteger)
value : new
BigInteger(
value.
toString());
}
/**
* convenience method to get this element as a float.
*
* @return get this element as a float.
* @throws NumberFormatException if the value contained is not a valid float.
*/
@
Override
public float
getAsFloat() {
return
isNumber() ?
getAsNumber().
floatValue() :
Float.
parseFloat(
getAsString());
}
/**
* convenience method to get this element as a primitive long.
*
* @return get this element as a primitive long.
* @throws NumberFormatException if the value contained is not a valid long.
*/
@
Override
public long
getAsLong() {
return
isNumber() ?
getAsNumber().
longValue() :
Long.
parseLong(
getAsString());
}
/**
* convenience method to get this element as a primitive short.
*
* @return get this element as a primitive short.
* @throws NumberFormatException if the value contained is not a valid short value.
*/
@
Override
public short
getAsShort() {
return
isNumber() ?
getAsNumber().
shortValue() :
Short.
parseShort(
getAsString());
}
/**
* convenience method to get this element as a primitive integer.
*
* @return get this element as a primitive integer.
* @throws NumberFormatException if the value contained is not a valid integer.
*/
@
Override
public int
getAsInt() {
return
isNumber() ?
getAsNumber().
intValue() :
Integer.
parseInt(
getAsString());
}
@
Override
public byte
getAsByte() {
return
isNumber() ?
getAsNumber().
byteValue() :
Byte.
parseByte(
getAsString());
}
@
Override
public char
getAsCharacter() {
return
getAsString().
charAt(0);
}
private static boolean
isPrimitiveOrString(
Object target) {
if (
target instanceof
String) {
return true;
}
Class<?>
classOfPrimitive =
target.
getClass();
for (
Class<?>
standardPrimitive :
PRIMITIVE_TYPES) {
if (
standardPrimitive.
isAssignableFrom(
classOfPrimitive)) {
return true;
}
}
return false;
}
@
Override
public int
hashCode() {
if (
value == null) {
return 31;
}
// Using recommended hashing algorithm from Effective Java for longs and doubles
if (
isIntegral(this)) {
long
value =
getAsNumber().
longValue();
return (int) (
value ^ (
value >>> 32));
}
if (
value instanceof
Number) {
long
value =
Double.
doubleToLongBits(
getAsNumber().
doubleValue());
return (int) (
value ^ (
value >>> 32));
}
return
value.
hashCode();
}
@
Override
public boolean
equals(
Object obj) {
if (this ==
obj) {
return true;
}
if (
obj == null ||
getClass() !=
obj.
getClass()) {
return false;
}
JsonPrimitive other = (
JsonPrimitive)
obj;
if (
value == null) {
return
other.
value == null;
}
if (
isIntegral(this) &&
isIntegral(
other)) {
return
getAsNumber().
longValue() ==
other.
getAsNumber().
longValue();
}
if (
value instanceof
Number &&
other.
value instanceof
Number) {
double
a =
getAsNumber().
doubleValue();
// Java standard types other than double return true for two NaN. So, need
// special handling for double.
double
b =
other.
getAsNumber().
doubleValue();
return
a ==
b || (
Double.
isNaN(
a) &&
Double.
isNaN(
b));
}
return
value.
equals(
other.
value);
}
/**
* Returns true if the specified number is an integral type
* (Long, Integer, Short, Byte, BigInteger)
*/
private static boolean
isIntegral(
JsonPrimitive primitive) {
if (
primitive.
value instanceof
Number) {
Number number = (
Number)
primitive.
value;
return
number instanceof
BigInteger ||
number instanceof
Long ||
number instanceof
Integer
||
number instanceof
Short ||
number instanceof
Byte;
}
return false;
}
}