net.minidev.asm.DefaultConverter Maven / Gradle / Ivy
package net.minidev.asm;
import net.minidev.asm.ex.ConvertException;
/**
* Provides utility methods to convert objects to different primitive types and their wrapper classes.
* It supports conversion from {@link Number} instances and {@link String} representations of numbers
* to their corresponding primitive types or wrapper classes. Conversion from types that are not supported
* will result in a {@link ConvertException}.
*/
public class DefaultConverter {
/**
* Default constructor
*/
public DefaultConverter() {
super();
}
/**
* Converts the given object to an {@code int}.
*
* @param obj the object to convert
* @return the converted int value, or 0 if the object is {@code null}
* @throws ConvertException if the object cannot be converted to an int
*/
public static int convertToint(Object obj) {
if (obj == null)
return 0;
if (obj instanceof Number)
return ((Number) obj).intValue();
if (obj instanceof String)
return Integer.parseInt((String) obj);
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to int");
}
/**
* Converts the given object to an {@link Integer}.
*
* @param obj the object to convert
* @return the converted Integer, or {@code null} if the object is {@code null}
* @throws ConvertException if the object cannot be converted to an Integer
*/
public static Integer convertToInt(Object obj) {
if (obj == null)
return null;
Class c = obj.getClass();
if (c == Integer.class)
return (Integer) obj;
if (obj instanceof Number)
return Integer.valueOf(((Number) obj).intValue());
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to Integer");
}
/**
* Converts the given object to a {@code short}.
*
* @param obj the object to convert
* @return the converted short value, or 0 if the object is {@code null}
* @throws ConvertException if the object cannot be converted to a short
*/
public static short convertToshort(Object obj) {
if (obj == null)
return 0;
if (obj instanceof Number)
return ((Number) obj).shortValue();
if (obj instanceof String)
return Short.parseShort((String) obj);
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to short");
}
/**
* Converts the given object to a {@code short}.
*
* @param obj the object to convert
* @return the converted short value, or 0 if the object is {@code null}
* @throws ConvertException if the object cannot be converted to a short
*/
public static Short convertToShort(Object obj) {
if (obj == null)
return null;
Class c = obj.getClass();
if (c == Short.class)
return (Short) obj;
if (obj instanceof Number)
return Short.valueOf(((Number) obj).shortValue());
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to Short");
}
/**
* Converts the given object to a {@code long}.
*
* @param obj the object to convert
* @return the converted long value, or 0 if the object is {@code null}
* @throws ConvertException if the object cannot be converted to a long
*/
public static long convertTolong(Object obj) {
if (obj == null)
return 0;
if (obj instanceof Number)
return ((Number) obj).longValue();
if (obj instanceof String)
return Long.parseLong((String) obj);
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to long");
}
/**
* Converts the given object to a {@link Long}.
*
* @param obj the object to convert
* @return the converted Long, or {@code null} if the object is {@code null}
* @throws ConvertException if the object cannot be converted to a Long
*/
public static Long convertToLong(Object obj) {
if (obj == null)
return null;
Class c = obj.getClass();
if (c == Long.class)
return (Long) obj;
if (obj instanceof Number)
return Long.valueOf(((Number) obj).longValue());
throw new ConvertException("Primitive: Can not convert value '" + obj+ "' As " + obj.getClass().getName() + " to Long");
}
/**
* Converts the given object to a {@code byte}.
*
* @param obj the object to convert
* @return the converted byte value, or 0 if the object is {@code null}
* @throws ConvertException if the object cannot be converted to a byte
*/
public static byte convertTobyte(Object obj) {
if (obj == null)
return 0;
if (obj instanceof Number)
return ((Number) obj).byteValue();
if (obj instanceof String)
return Byte.parseByte((String) obj);
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to byte");
}
/**
* Converts the given object to a {@link Byte}.
*
* @param obj the object to convert
* @return the converted Byte, or {@code null} if the object is {@code null}
* @throws ConvertException if the object cannot be converted to a Byte
*/
public static Byte convertToByte(Object obj) {
if (obj == null)
return null;
Class c = obj.getClass();
if (c == Byte.class)
return (Byte) obj;
if (obj instanceof Number)
return Byte.valueOf(((Number) obj).byteValue());
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to Byte");
}
/**
* Converts the given object to a {@code float}.
*
* @param obj the object to convert
* @return the converted float value, or 0f if the object is {@code null}
* @throws ConvertException if the object cannot be converted to a float
*/
public static float convertTofloat(Object obj) {
if (obj == null)
return 0f;
if (obj instanceof Number)
return ((Number) obj).floatValue();
if (obj instanceof String)
return Float.parseFloat((String) obj);
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to float");
}
/**
* Converts the given object to a {@link Byte}.
*
* @param obj the object to convert
* @return the converted Byte, or {@code null} if the object is {@code null}
* @throws ConvertException if the object cannot be converted to a Byte
*/
public static Float convertToFloat(Object obj) {
if (obj == null)
return null;
Class c = obj.getClass();
if (c == Float.class)
return (Float) obj;
if (obj instanceof Number)
return Float.valueOf(((Number) obj).floatValue());
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to Float");
}
/**
* Converts the given object to a {@code double}.
*
* @param obj the object to convert
* @return the converted double value, or 0.0 if the object is {@code null}
* @throws ConvertException if the object cannot be converted to a double
*/
public static double convertTodouble(Object obj) {
if (obj == null)
return 0.0;
if (obj instanceof Number)
return ((Number) obj).doubleValue();
if (obj instanceof String)
return Double.parseDouble((String) obj);
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to float");
}
/**
* Converts the given object to a {@link Double}.
*
* @param obj the object to convert
* @return the converted Double, or {@code null} if the object is {@code null}
* @throws ConvertException if the object cannot be converted to a Double
*/
public static Double convertToDouble(Object obj) {
if (obj == null)
return null;
Class c = obj.getClass();
if (c == Double.class)
return (Double) obj;
if (obj instanceof Number)
return Double.valueOf(((Number) obj).doubleValue());
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to Float");
}
/**
* Converts the given object to a {@code char}.
*
* @param obj the object to convert
* @return the converted char value, or a space character if the object is {@code null} or the string is empty
* @throws ConvertException if the object cannot be converted to a char
*/
public static char convertTochar(Object obj) {
if (obj == null)
return ' ';
if (obj instanceof String)
if (((String) obj).length() > 0)
return ((String) obj).charAt(0);
else
return ' ';
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to char");
}
/**
* Converts the given object to a {@link Character}.
*
* @param obj the object to convert
* @return the converted Character, or {@code null} if the object is {@code null}
* @throws ConvertException if the object cannot be converted to a Character
*/
public static Character convertToChar(Object obj) {
if (obj == null)
return null;
Class c = obj.getClass();
if (c == Character.class)
return (Character) obj;
if (obj instanceof String)
if (((String) obj).length() > 0)
return ((String) obj).charAt(0);
else
return ' ';
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to Character");
}
/**
* Converts the given object to a {@code boolean}.
*
* @param obj the object to convert
* @return the converted boolean value, false if the object is {@code null} or represents the numeric value 0
* @throws ConvertException if the object cannot be converted to a boolean
*/
public static boolean convertTobool(Object obj) {
if (obj == null)
return false;
if (obj.getClass() == Boolean.class)
return ((Boolean) obj).booleanValue();
if (obj instanceof String)
return Boolean.parseBoolean((String) obj);
if (obj instanceof Number) {
if (obj.toString().equals("0"))
return false;
else
return true;
}
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to boolean");
}
/**
* Converts the given object to a {@link Boolean}.
*
* @param obj the object to convert
* @return the converted Boolean, or {@code null} if the object is {@code null}
* @throws ConvertException if the object cannot be converted to a Boolean
*/
public static Boolean convertToBool(Object obj) {
if (obj == null)
return null;
Class c = obj.getClass();
if (c == Boolean.class)
return (Boolean) obj;
if (obj instanceof String)
return Boolean.parseBoolean((String) obj);
throw new ConvertException("Primitive: Can not convert " + obj.getClass().getName() + " to Boolean");
}
}