/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.activemq.util;
import java.math.BigInteger;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import org.apache.activemq.command.ActiveMQDestination;
import org.fusesource.hawtbuf.UTF8Buffer;
/**
* Type conversion support for ActiveMQ.
*/
public final class TypeConversionSupport {
private static final Converter IDENTITY_CONVERTER = new Converter() {
@Override
public Object convert(Object value) {
return value;
}
};
private static class ConversionKey {
final Class<?> from;
final Class<?> to;
final int hashCode;
public ConversionKey(Class<?> from, Class<?> to) {
this.from = from;
this.to = to;
this.hashCode = from.hashCode() ^ (to.hashCode() << 1);
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
ConversionKey other = (ConversionKey) obj;
if (from == null) {
if (other.from != null)
return false;
} else if (!from.equals(other.from))
return false;
if (to == null) {
if (other.to != null)
return false;
} else if (!to.equals(other.to))
return false;
return true;
}
@Override
public int hashCode() {
return hashCode;
}
}
public interface Converter {
Object convert(Object value);
}
private static final Map<ConversionKey, Converter> CONVERSION_MAP = new HashMap<ConversionKey, Converter>();
static {
Converter toStringConverter = new Converter() {
@Override
public Object convert(Object value) {
return value.toString();
}
};
CONVERSION_MAP.put(new ConversionKey(Boolean.class, String.class), toStringConverter);
CONVERSION_MAP.put(new ConversionKey(Byte.class, String.class), toStringConverter);
CONVERSION_MAP.put(new ConversionKey(Short.class, String.class), toStringConverter);
CONVERSION_MAP.put(new ConversionKey(Integer.class, String.class), toStringConverter);
CONVERSION_MAP.put(new ConversionKey(Long.class, String.class), toStringConverter);
CONVERSION_MAP.put(new ConversionKey(Float.class, String.class), toStringConverter);
CONVERSION_MAP.put(new ConversionKey(Double.class, String.class), toStringConverter);
CONVERSION_MAP.put(new ConversionKey(UTF8Buffer.class, String.class), toStringConverter);
CONVERSION_MAP.put(new ConversionKey(URI.class, String.class), toStringConverter);
CONVERSION_MAP.put(new ConversionKey(BigInteger.class, String.class), toStringConverter);
CONVERSION_MAP.put(new ConversionKey(String.class, Boolean.class), new Converter() {
@Override
public Object convert(Object value) {
return Boolean.valueOf((String)value);
}
});
CONVERSION_MAP.put(new ConversionKey(String.class, Byte.class), new Converter() {
@Override
public Object convert(Object value) {
return Byte.valueOf((String)value);
}
});
CONVERSION_MAP.put(new ConversionKey(String.class, Short.class), new Converter() {
@Override
public Object convert(Object value) {
return Short.valueOf((String)value);
}
});
CONVERSION_MAP.put(new ConversionKey(String.class, Integer.class), new Converter() {
@Override
public Object convert(Object value) {
return Integer.valueOf((String)value);
}
});
CONVERSION_MAP.put(new ConversionKey(String.class, Long.class), new Converter() {
@Override
public Object convert(Object value) {
return Long.valueOf((String)value);
}
});
CONVERSION_MAP.put(new ConversionKey(String.class, Float.class), new Converter() {
@Override
public Object convert(Object value) {
return Float.valueOf((String)value);
}
});
CONVERSION_MAP.put(new ConversionKey(String.class, Double.class), new Converter() {
@Override
public Object convert(Object value) {
return Double.valueOf((String)value);
}
});
Converter longConverter = new Converter() {
@Override
public Object convert(Object value) {
return Long.valueOf(((Number)value).longValue());
}
};
CONVERSION_MAP.put(new ConversionKey(Byte.class, Long.class), longConverter);
CONVERSION_MAP.put(new ConversionKey(Short.class, Long.class), longConverter);
CONVERSION_MAP.put(new ConversionKey(Integer.class, Long.class), longConverter);
CONVERSION_MAP.put(new ConversionKey(Date.class, Long.class), new Converter() {
@Override
public Object convert(Object value) {
return Long.valueOf(((Date)value).getTime());
}
});
Converter intConverter = new Converter() {
@Override
public Object convert(Object value) {
return Integer.valueOf(((Number)value).intValue());
}
};
CONVERSION_MAP.put(new ConversionKey(Byte.class, Integer.class), intConverter);
CONVERSION_MAP.put(new ConversionKey(Short.class, Integer.class), intConverter);
CONVERSION_MAP.put(new ConversionKey(Byte.class, Short.class), new Converter() {
@Override
public Object convert(Object value) {
return Short.valueOf(((Number)value).shortValue());
}
});
CONVERSION_MAP.put(new ConversionKey(Float.class, Double.class), new Converter() {
@Override
public Object convert(Object value) {
return new Double(((Number)value).doubleValue());
}
});
CONVERSION_MAP.put(new ConversionKey(String.class, ActiveMQDestination.class), new Converter() {
@Override
public Object convert(Object value) {
return ActiveMQDestination.createDestination((String)value, ActiveMQDestination.QUEUE_TYPE);
}
});
CONVERSION_MAP.put(new ConversionKey(String.class, URI.class), new Converter() {
@Override
public Object convert(Object value) {
String text = value.toString();
try {
return new URI(text);
} catch (URISyntaxException e) {
throw new RuntimeException(e);
}
}
});
}
private TypeConversionSupport() {
}
public static Object convert(Object value, Class<?> to) {
if (value == null) {
// lets avoid NullPointerException when converting to boolean for null values
if (boolean.class.isAssignableFrom(to)) {
return Boolean.FALSE;
}
return null;
}
// eager same instance type test to avoid the overhead of invoking the type converter
// if already same type
if (to.isInstance(value)) {
return to.cast(value);
}
// lookup converter
Converter c = lookupConverter(value.getClass(), to);
if (c != null) {
return c.convert(value);
} else {
return null;
}
}
public static Converter lookupConverter(Class<?> from, Class<?> to) {
// use wrapped type for primitives
if (from.isPrimitive()) {
from = convertPrimitiveTypeToWrapperType(from);
}
if (to.isPrimitive()) {
to = convertPrimitiveTypeToWrapperType(to);
}
if (from.equals(to)) {
return IDENTITY_CONVERTER;
}
return CONVERSION_MAP.get(new ConversionKey(from, to));
}
/**
* Converts primitive types such as int to its wrapper type like
* {@link Integer}
*/
private static Class<?> convertPrimitiveTypeToWrapperType(Class<?> type) {
Class<?> rc = type;
if (type.isPrimitive()) {
if (type == int.class) {
rc = Integer.class;
} else if (type == long.class) {
rc = Long.class;
} else if (type == double.class) {
rc = Double.class;
} else if (type == float.class) {
rc = Float.class;
} else if (type == short.class) {
rc = Short.class;
} else if (type == byte.class) {
rc = Byte.class;
} else if (type == boolean.class) {
rc = Boolean.class;
}
}
return rc;
}
}