com.cedarsoftware.util.Converter Maven / Gradle / Ivy
package com.cedarsoftware.util;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.Calendar;
import java.util.Date;
/**
* Handy conversion utilities
*
* @author John DeRegnaucourt ([email protected])
*
* Copyright (c) Cedar Software LLC
*
* 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.
*/
public final class Converter
{
/**
* Turn the passed in value to the class indicated. This will allow, for
* example, a String value to be passed in and have it coerced to a Long.
*
* Examples:
* Long x = convert("35", Long.class);
* Date d = convert("2015/01/01", Date.class)
* int y = convert(45.0, int.class)
* String date = convert(date, String.class)
* String date = convert(calendar, String.class)
* Short t = convert(true, short.class); // returns (short) 1 or (short) 0
* Long date = convert(calendar, long.class); // get calendar's time into long
*
* @param fromInstance A value used to create the targetType, even though it may
* not (most likely will not) be the same data type as the targetType
* @param toType Class which indicates the targeted (final) data type.
* Please note that in addition to the 8 Java primitives, the targeted class
* can also be Date.class, String.class, BigInteger.class, and BigDecimal.class.
* The primitive class can be either primitive class or primitive wrapper class,
* however, the returned value will always [obviously] be a primitive wrapper.
* @return An instanceof targetType class, based upon the value passed in.
*/
public static Object convert(Object fromInstance, Class toType)
{
if (toType == null)
{
throw new IllegalArgumentException("Type cannot be null in Converter.convert(value, type)");
}
if (fromInstance == null)
{
return null;
}
switch(toType.getName())
{
case "byte":
case "java.lang.Byte":
try
{
if (fromInstance instanceof Byte)
{
return fromInstance;
}
else if (fromInstance instanceof Number)
{
return ((Number)fromInstance).byteValue();
}
else if (fromInstance instanceof String)
{
return Byte.valueOf(((String) fromInstance).trim());
}
else if (fromInstance instanceof Boolean)
{
return (Boolean) fromInstance ? (byte) 1 : (byte) 0;
}
}
catch(Exception e)
{
throw new IllegalArgumentException("value [" + fromInstance.getClass().getName() + "] could not be converted to a 'Byte'", e);
}
throw new IllegalArgumentException("Unsupported value type [" + fromInstance.getClass().getName() + "] attempting to convert to 'Byte'");
case "short":
case "java.lang.Short":
try
{
if (fromInstance instanceof Short)
{
return fromInstance;
}
else if (fromInstance instanceof Number)
{
return ((Number)fromInstance).shortValue();
}
else if (fromInstance instanceof String)
{
return Short.valueOf(((String) fromInstance).trim());
}
else if (fromInstance instanceof Boolean)
{
return (Boolean) fromInstance ? (short) 1 : (short) 0;
}
}
catch(Exception e)
{
throw new IllegalArgumentException("value [" + fromInstance.getClass().getName() + "] could not be converted to a 'Short'", e);
}
throw new IllegalArgumentException("Unsupported value type [" + fromInstance.getClass().getName() + "] attempting to convert to 'Short'");
case "int":
case "java.lang.Integer":
try
{
if (fromInstance instanceof Integer)
{
return fromInstance;
}
else if (fromInstance instanceof Number)
{
return ((Number)fromInstance).intValue();
}
else if (fromInstance instanceof String)
{
return Integer.valueOf(((String) fromInstance).trim());
}
else if (fromInstance instanceof Boolean)
{
return (Boolean) fromInstance ? 1 : 0;
}
}
catch(Exception e)
{
throw new IllegalArgumentException("value [" + fromInstance.getClass().getName() + "] could not be converted to an 'Integer'", e);
}
throw new IllegalArgumentException("Unsupported value type [" + fromInstance.getClass().getName() + "] attempting to convert to 'Integer'");
case "long":
case "java.lang.Long":
try
{
if (fromInstance instanceof Long)
{
return fromInstance;
}
else if (fromInstance instanceof Number)
{
return ((Number)fromInstance).longValue();
}
else if (fromInstance instanceof String)
{
return Long.valueOf(((String) fromInstance).trim());
}
else if (fromInstance instanceof Date)
{
return ((Date)fromInstance).getTime();
}
else if (fromInstance instanceof Boolean)
{
return (Boolean) fromInstance ? 1L : 0L;
}
else if (fromInstance instanceof Calendar)
{
return ((Calendar)fromInstance).getTime().getTime();
}
}
catch(Exception e)
{
throw new IllegalArgumentException("value [" + fromInstance.getClass().getName() + "] could not be converted to a 'Long'", e);
}
throw new IllegalArgumentException("Unsupported value type [" + fromInstance.getClass().getName() + "] attempting to convert to 'Long'");
case "java.lang.String":
if (fromInstance instanceof String)
{
return fromInstance;
}
else if (fromInstance instanceof BigDecimal)
{
return ((BigDecimal) fromInstance).stripTrailingZeros().toPlainString();
}
else if (fromInstance instanceof Number || fromInstance instanceof Boolean)
{
return fromInstance.toString();
}
else if (fromInstance instanceof Date)
{
return SafeSimpleDateFormat.getDateFormat("yyyy-MM-dd'T'HH:mm:ss").format(fromInstance);
}
else if (fromInstance instanceof Calendar)
{
return SafeSimpleDateFormat.getDateFormat("yyyy-MM-dd'T'HH:mm:ss").format(((Calendar)fromInstance).getTime());
}
else if (fromInstance instanceof Character)
{
return "" + fromInstance;
}
throw new IllegalArgumentException("Unsupported value type [" + fromInstance.getClass().getName() + "] attempting to convert to 'String'");
case "java.math.BigDecimal":
try
{
if (fromInstance instanceof BigDecimal)
{
return fromInstance;
}
else if (fromInstance instanceof BigInteger)
{
return new BigDecimal((BigInteger) fromInstance);
}
else if (fromInstance instanceof String)
{
return new BigDecimal(((String) fromInstance).trim());
}
else if (fromInstance instanceof Number)
{
return new BigDecimal(((Number) fromInstance).doubleValue());
}
else if (fromInstance instanceof Boolean)
{
return (Boolean) fromInstance ? BigDecimal.ONE : BigDecimal.ZERO;
}
else if (fromInstance instanceof Date)
{
return new BigDecimal(((Date)fromInstance).getTime());
}
else if (fromInstance instanceof Calendar)
{
return new BigDecimal(((Calendar)fromInstance).getTime().getTime());
}
}
catch(Exception e)
{
throw new IllegalArgumentException("value [" + fromInstance.getClass().getName() + "] could not be converted to a 'BigDecimal'", e);
}
throw new IllegalArgumentException("Unsupported value type [" + fromInstance.getClass().getName() + "] attempting to convert to 'BigDecimal'");
case "java.math.BigInteger":
try
{
if (fromInstance instanceof BigInteger)
{
return fromInstance;
}
else if (fromInstance instanceof BigDecimal)
{
return ((BigDecimal) fromInstance).toBigInteger();
}
else if (fromInstance instanceof String)
{
return new BigInteger(((String) fromInstance).trim());
}
else if (fromInstance instanceof Number)
{
return new BigInteger(Long.toString(((Number) fromInstance).longValue()));
}
else if (fromInstance instanceof Boolean)
{
return (Boolean) fromInstance ? BigInteger.ONE : BigInteger.ZERO;
}
else if (fromInstance instanceof Date)
{
return new BigInteger(Long.toString(((Date) fromInstance).getTime()));
}
else if (fromInstance instanceof Calendar)
{
return new BigInteger(Long.toString(((Calendar) fromInstance).getTime().getTime()));
}
}
catch(Exception e)
{
throw new IllegalArgumentException("value [" + fromInstance.getClass().getName() + "] could not be converted to a 'BigInteger'", e);
}
throw new IllegalArgumentException("Unsupported value type [" + fromInstance.getClass().getName() + "] attempting to convert to 'BigInteger'");
case "java.util.Date":
try
{
if (fromInstance instanceof java.sql.Date)
{ // convert from java.sql.Date to java.util.Date
return new Date(((java.sql.Date)fromInstance).getTime());
}
else if (fromInstance instanceof Date)
{
return fromInstance;
}
else if (fromInstance instanceof String)
{
return DateUtilities.parseDate(((String) fromInstance).trim());
}
else if (fromInstance instanceof Calendar)
{
return ((Calendar) fromInstance).getTime();
}
else if (fromInstance instanceof Long)
{
return new Date((Long) fromInstance);
}
throw new IllegalArgumentException("Unsupported value type [" + fromInstance.getClass().getName() + "] attempting to convert to 'Date'");
}
catch(Exception e)
{
throw new IllegalArgumentException("value [" + fromInstance.getClass().getName() + "] could not be converted to a 'Date'", e);
}
case "java.sql.Date":
try
{
if (fromInstance instanceof java.sql.Date)
{
return fromInstance;
}
else if (fromInstance instanceof Date)
{ // convert from java.util.Date to java.sql.Date
return new java.sql.Date(((Date)fromInstance).getTime());
}
else if (fromInstance instanceof String)
{
Date date = DateUtilities.parseDate(((String) fromInstance).trim());
return new java.sql.Date(date.getTime());
}
else if (fromInstance instanceof Calendar)
{
return new java.sql.Date(((Calendar) fromInstance).getTime().getTime());
}
else if (fromInstance instanceof Long)
{
return new java.sql.Date((Long) fromInstance);
}
throw new IllegalArgumentException("Unsupported value type [" + fromInstance.getClass().getName() + "] attempting to convert to 'java.sql.Date'");
}
catch(Exception e)
{
throw new IllegalArgumentException("value [" + fromInstance.getClass().getName() + "] could not be converted to a 'java.sql.Date'", e);
}
case "float":
case "java.lang.Float":
try
{
if (fromInstance instanceof Float)
{
return fromInstance;
}
else if (fromInstance instanceof Number)
{
return ((Number)fromInstance).floatValue();
}
else if (fromInstance instanceof String)
{
return Float.valueOf(((String) fromInstance).trim());
}
else if (fromInstance instanceof Boolean)
{
return (Boolean) fromInstance ? 1.0f : 0.0f;
}
}
catch(Exception e)
{
throw new IllegalArgumentException("value [" + fromInstance.getClass().getName() + "] could not be converted to a 'Float'", e);
}
throw new IllegalArgumentException("Unsupported value type [" + fromInstance.getClass().getName() + "] attempting to convert to 'Float'");
case "double":
case "java.lang.Double":
try
{
if (fromInstance instanceof Double)
{
return fromInstance;
}
else if (fromInstance instanceof Number)
{
return ((Number)fromInstance).doubleValue();
}
else if (fromInstance instanceof String)
{
return Double.valueOf(((String) fromInstance).trim());
}
else if (fromInstance instanceof Boolean)
{
return (Boolean) fromInstance ? 1.0d : 0.0d;
}
}
catch(Exception e)
{
throw new IllegalArgumentException("value [" + fromInstance.getClass().getName() + "] could not be converted to a 'Double'", e);
}
throw new IllegalArgumentException("Unsupported value type [" + fromInstance.getClass().getName() + "] attempting to convert to 'Double'");
}
throw new IllegalArgumentException("Unsupported type '" + toType.getName() + "' for conversion");
}
}
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