/**
* jetbrick-template
* http://subchen.github.io/jetbrick-template/
*
* Copyright 2010-2014 Guoqiang Chen. All rights reserved.
* Email: subchen@gmail.com
*
* 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 jetbrick.template.parser.support;
import java.util.HashMap;
import java.util.Map;
/**
* <p>
* Unary Operator. <br/>
* {@link http://docs.oracle.com/javase/specs/jls/se7/html/jls-5.html#jls-5.6.1}<br/>
* <ul>
* <li>Each dimension expression in an array creation expression</li>
* <li>The index expression in an array access expression </li>
* <li>The operand of a unary plus operator + </li>
* <li>The operand of a unary minus operator - </li>
* <li>The operand of a bitwise complement operator ~ </li>
* <li>Each operand, separately, of a shift operator >>, >>>, or << </li>
* </ul>
* </p>
*
* <p>
* Binary Operator. <br/>
* {@link http://docs.oracle.com/javase/specs/jls/se7/html/jls-5.html#jls-5.6.2}<br/>
* <ul>
* <li>The multiplicative operators *, / and % </li>
* <li>The addition and subtraction operators for numeric types + and - </li>
* <li>The numerical comparison operators <, <=, >, and >= </li>
* <li>The numerical equality operators == and != </li>
* <li>The integer bitwise operators &, ^, and | </li>
* <li>In certain cases, the conditional operator ? : </li>
* </ul>
* </p>
*
* <p>
* String "+" Operator. <br/>
* {@link http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.18.1}<br/>
* </p>
*/
public class PromotionUtils {
private static final Map<Class<?>, Class<?>> unary_promotion_map;
// +, -, ~
public static Class<?> get_unary_basic(Class<?> klass, String op) {
// http://docs.oracle.com/javase/specs/jls/se7/html/jls-5.html#jls-5.6.1
switch (op.charAt(0)) {
case '+':
case '-':
return unary_promotion_map.get(klass);
case '~':
if (NumberClassUtils.isIntegerClass(klass)) {
return unary_promotion_map.get(klass);
}
}
return null;
}
// ++, --
public static Class<?> get_unary_inc_dec(Class<?> klass, String op) {
// ++, --
switch (op.charAt(0)) {
case '+':
case '-':
if (NumberClassUtils.isNumbericClass(klass)) {
return PrimitiveClassUtils.asUnboxedClass(klass);
}
}
return null;
}
// +, -, *, /, %
public static Class<?> get_binary_basic(Class<?> lhs, Class<?> rhs, String op) {
switch (op.charAt(0)) {
case '+':
// http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.18.1
if (String.class.equals(lhs) || String.class.equals(rhs)) {
if (Void.TYPE.equals(lhs) || Void.TYPE.equals(rhs)) return null;
return String.class;
}
case '-':
case '*':
case '/':
case '%':
// http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.18.2
// http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.17
return to_binary_promotion(lhs, rhs);
}
return null;
}
// <<, >>, >>>
public static Class<?> get_binary_shift(Class<?> lhs, Class<?> rhs, String op) {
// http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.19
if (NumberClassUtils.isIntegerClass(lhs) && NumberClassUtils.isIntegerClass(rhs)) {
return PrimitiveClassUtils.asUnboxedClass(lhs);
}
return null;
}
// &, |, ^
public static Class<?> get_binary_bitwise(Class<?> lhs, Class<?> rhs, String op) {
switch (op.charAt(0)) {
case '&':
case '|':
case '^':
// http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.22.2
if (Boolean.TYPE.equals(lhs) && Boolean.TYPE.equals(rhs)) {
return Boolean.TYPE;
}
// http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.22.1
if (NumberClassUtils.isIntegerClass(lhs) && NumberClassUtils.isIntegerClass(rhs)) {
return to_binary_promotion(lhs, rhs);
}
}
return null;
}
// <, <=, >, >=
public static Class<?> get_binary_compare(Class<?> lhs, Class<?> rhs, String op) {
// http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.20.1
if (NumberClassUtils.isNumbericClass(lhs) || NumberClassUtils.isNumbericClass(rhs)) {
return Boolean.TYPE;
}
return null;
}
// http://docs.oracle.com/javase/specs/jls/se7/html/jls-5.html#jls-5.6.2
private static Class<?> to_binary_promotion(Class<?> lhs, Class<?> rhs) {
if (!NumberClassUtils.isNumbericClass(lhs)) {
return null;
}
if (!NumberClassUtils.isNumbericClass(rhs)) {
return null;
}
lhs = PrimitiveClassUtils.asUnboxedClass(lhs);
rhs = PrimitiveClassUtils.asUnboxedClass(rhs);
if (Double.TYPE.equals(lhs) || Double.TYPE.equals(rhs)) {
return Double.TYPE;
} else if (Float.TYPE.equals(lhs) || Float.TYPE.equals(rhs)) {
return Float.class;
} else if (Long.TYPE.equals(lhs) || Long.TYPE.equals(rhs)) {
return Long.TYPE;
} else {
return Integer.TYPE;
}
}
// 得到三元表达式的返回类型，即：简单计算两个class的公共父类或者公共接口。
// http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.25
public static TypedKlass getResultClassForConditionalOperator(TypedKlass k1, TypedKlass k2) {
if (k1 == k2) return k1;
Class<?> c1 = (k1 == null) ? null : k1.getKlass();
Class<?> c2 = (k2 == null) ? null : k2.getKlass();
if (c1 == null) {
if (c2.isPrimitive()) {
return TypedKlass.create(PrimitiveClassUtils.asBoxedClass(c2));
}
return k2;
}
if (c2 == null) {
if (c1.isPrimitive()) {
return TypedKlass.create(PrimitiveClassUtils.asBoxedClass(c1));
}
return k1;
}
if (NumberClassUtils.isNumbericClass(c1) && NumberClassUtils.isNumbericClass(c2)) {
c1 = PrimitiveClassUtils.asUnboxedClass(c1);
c2 = PrimitiveClassUtils.asUnboxedClass(c2);
return TypedKlass.create(to_binary_promotion(c1, c2));
}
if (c1.isAssignableFrom(c2)) return k1;
if (c2.isAssignableFrom(c1)) return k2;
// 注意：后面的算法不是很好，应该返回的是一个Set<Class>，而不是一个Class
Class<?> c1_super = c1.getSuperclass();
if (c1_super != null && c1_super.isAssignableFrom(c2)) {
return TypedKlass.create(c1_super);
}
Class<?> c2_super = c2.getSuperclass();
if (c2_super != null && c2_super.isAssignableFrom(c1)) {
return TypedKlass.create(c2_super);
}
for (Class<?> c : c1.getInterfaces()) {
if (c.isAssignableFrom(c2)) {
return TypedKlass.create(c);
}
}
for (Class<?> c : c2.getInterfaces()) {
if (c.isAssignableFrom(c1)) {
return TypedKlass.create(c);
}
}
return TypedKlass.Object;
}
static {
// http://docs.oracle.com/javase/specs/jls/se7/html/jls-5.html#jls-5.6.2
unary_promotion_map = new HashMap<Class<?>, Class<?>>(32);
unary_promotion_map.put(Byte.TYPE, Integer.TYPE);
unary_promotion_map.put(Short.TYPE, Integer.TYPE);
unary_promotion_map.put(Character.TYPE, Integer.TYPE);
unary_promotion_map.put(Integer.TYPE, Integer.TYPE);
unary_promotion_map.put(Long.TYPE, Long.TYPE);
unary_promotion_map.put(Float.TYPE, Float.TYPE);
unary_promotion_map.put(Double.TYPE, Double.TYPE);
unary_promotion_map.put(Byte.class, Integer.TYPE);
unary_promotion_map.put(Short.class, Integer.TYPE);
unary_promotion_map.put(Character.class, Integer.TYPE);
unary_promotion_map.put(Integer.class, Integer.TYPE);
unary_promotion_map.put(Long.class, Long.TYPE);
unary_promotion_map.put(Float.class, Float.TYPE);
unary_promotion_map.put(Double.class, Double.TYPE);
}
}