Casting (MMBase2 Utils 2.0.0

java.lang.Object
- org.mmbase.util.Casting

```
public class Casting
extends Object
```
Collects MMBase specific 'cast' information, as static to... functions. This is used (and used to be implemented) in MMObjectNode. But this functionality is more generic to MMbase.

Since:

MMBase-1.6

Version:

$Id$

Author:

Michiel Meeuwissen

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`Casting.ListWrapper`
`(package private) static class`	`Casting.StringSerializableInputStream` A SerializableInputStream where the toString represents the (escaped) contents of the stream itself.
`static class`	`Casting.StringWrapper` Wraps a String with an 'Escaper'.
`static interface`	`Casting.Unwrappable` Clases implementing this will not be wrapped by `wrap(java.lang.Object, org.mmbase.util.transformers.CharTransformer)`, even if the e.g.

Field Summary

Fields
Modifier and Type	Field and Description
`static Pattern`	`BOOLEAN_PATTERN`
`(package private) static DocumentBuilder`	`DOCUMENTBUILDER`
`static Pattern`	`DOUBLE_PATTERN`
`static ThreadLocal<DateFormat>`	`ISO_8601_DATE`
`static ThreadLocal<DateFormat>`	`ISO_8601_LOOSE` A Date formatter that creates a date based on a ISO 8601 date and a ISO 8601 time.
`static ThreadLocal<DateFormat>`	`ISO_8601_TIME`
`static ThreadLocal<DateFormat>`	`ISO_8601_UTC` A Date formatter that creates a ISO 8601 datetime according to UTC/GMT.

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static boolean`	`canCast(Class<?> from, Class<?> to)` This method should report whether `toType(java.lang.Class<C>, java.lang.Object)` is implemented for given 2 classes.
`static boolean`	`equals(Object o1, Object o2)`
`static String`	`escape(CharTransformer escaper, CharSequence string)`
`static boolean`	`isStringRepresentable(Class<?> type)` Whether or not Casting can more or less reliably cast a certain type to String and back.
`static boolean`	`isType(Class type, Object value)` Returns whether the passed object is of the given class.
`static void`	`setHelper(Caster h)`
`static boolean`	`toBoolean(Object b)` Convert an object to a `boolean`.
`static byte[]`	`toByte(Object obj)` Convert an object to a byte array.
`static Collection`	`toCollection(Object o)`
`static Collection`	`toCollection(Object o, String delimiter)` Transforms an object to a collection.
`static Date`	`toDate(Object d)` Convert an object to a `Date`.
`static BigDecimal`	`toDecimal(Object i)`
`static double`	`toDouble(Object i)` Convert an object to an `double`.
`static double`	`toDouble(Object i, double def)` Convert an object to an `double`.
`static float`	`toFloat(Object i)` Convert an object to an `float`.
`static float`	`toFloat(Object i, float def)` Convert an object to an `float`.
`static InputStream`	`toInputStream(Object obj)`
`static int`	`toInt(Object i)` Convert an object to an `int`.
`static int`	`toInt(Object i, int def)` Convert an object to an `int`.
`static Integer`	`toInteger(Object i)` Convert an object to an Integer.
`static List`	`toList(Object o)` Convert an object to a List.
`static List`	`toList(Object o, String delimiter)` As `toList(Object)` but with one extra argument.
`static long`	`toLong(Object i)` Convert an object to a `long`.
`static long`	`toLong(Object i, long def)` Convert an object to a `long`.
`static Map`	`toMap(Object o)`
`static SerializableInputStream`	`toSerializableInputStream(Object obj)`
`static String`	`toString(Object o)` Convert an object to a String.
`static StringBuffer`	`toStringBuffer(StringBuffer buffer, Object o)` Convert an object to a string, using a StringBuffer.
`static StringBuilder`	`toStringBuilder(StringBuilder buffer, Object o)` Convert an object to a string, using a StringBuilder
`static <C> C`	`toType(Class<C> type, Object value)` Tries to 'cast' an object for use with the provided class.
`static <C> C`	`toType(Class<C> type, Object cloud, Object value)` Tries to 'cast' an object for use with the provided class.
`static Writer`	`toWriter(Writer writer, Object o)` Convert an object to a string, using a Writer.
`static Document`	`toXML(Object o)` Convert the value to a `Document` object.
`static Object`	`unWrap(Object o)` When you want to undo the wrapping, this method can be used.
`static Object`	`wrap(Object o, CharTransformer escaper)` Wraps an object in another object with a toString as we desire.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - ISO_8601_LOOSE
```
public static final ThreadLocal<DateFormat> ISO_8601_LOOSE
```
    A Date formatter that creates a date based on a ISO 8601 date and a ISO 8601 time. I.e. 2004-12-01 14:30:00. It is NOT 100% ISO 8601, as opposed to ISO_8601_UTC, as the standard actually requires a 'T' to be placed between the date and the time. The date given is the date for the local (server) time. Use this formatter if you want to display user-friendly dates in local time. XXX: According to http://en.wikipedia.org/wiki/ISO_8601, the standard allows ' ' in stead of 'T' if no misunderstanding arises, which is the case here. So I don't think this is 'loose'.
  - ISO_8601_UTC
```
public static final ThreadLocal<DateFormat> ISO_8601_UTC
```
    A Date formatter that creates a ISO 8601 datetime according to UTC/GMT. I.e. 2004-12-01T14:30:00Z. This is 100% ISO 8601, as opposed to ISO_8601_LOOSE. Use this formatter if you want to export dates. XXX: Hmm, we parse with UTC now, while we don't store them as such.
  - ISO_8601_DATE
```
public static final ThreadLocal<DateFormat> ISO_8601_DATE
```
  - ISO_8601_TIME
```
public static final ThreadLocal<DateFormat> ISO_8601_TIME
```
  - DOCUMENTBUILDER
```
static DocumentBuilder DOCUMENTBUILDER
```
  - BOOLEAN_PATTERN
```
public static final Pattern BOOLEAN_PATTERN
```
  - DOUBLE_PATTERN
```
public static final Pattern DOUBLE_PATTERN
```
- Method Detail
  - isType
```
public static boolean isType(Class type,
                             Object value)
```
    Returns whether the passed object is of the given class. Unlike Class instanceof this also includes Object Types that are representative for primitive types (i.e. Integer for int).
    
    Parameters:
    
    type - the type (class) to check
    
    value - the value whose type to check
    
    Returns:
    
    true if compatible
    
    Since:
    
    MMBase-1.8
  - toType
```
public static <C> C toType(Class<C> type,
                           Object value)
```
    Tries to 'cast' an object for use with the provided class. E.g. if value is a String, but the type passed is Integer, then the string is act to an Integer. If the type passed is a primitive type, the object is cast to an Object Types that is representative for that type (i.e. Integer for int).
    
    Parameters:
    
    type - the type (class)
    
    value - The value to be converted
    
    Returns:
    
    value the converted value
    
    Since:
    
    MMBase-1.8
  - toType
```
public static <C> C toType(Class<C> type,
                           Object cloud,
                           Object value)
```
    Tries to 'cast' an object for use with the provided class. E.g. if value is a String, but the type passed is Integer, then the string is act to an Integer. If the type passed is a primitive type, the object is cast to an Object Types that is representative for that type (i.e. Integer for int).
    
    Parameters:
    
    type - the type (class)
    
    cloud - When casting to Node, a cloud may be needed. May be null, for an anonymous cloud to be tried.
    
    value - The value to be converted
    
    Returns:
    
    value the converted value
    
    Since:
    
    MMBase-1.8
  - canCast
```
public static boolean canCast(Class<?> from,
                              Class<?> to)
```
    This method should report whether toType(java.lang.Class<C>, java.lang.Object) is implemented for given 2 classes. It is not yet fully implemented.
    
    Since:
    
    MMBase-1.9.2
  - isStringRepresentable
```
public static boolean isStringRepresentable(Class<?> type)
```
    Whether or not Casting can more or less reliably cast a certain type to String and back. For collection types also the entries of the collection must be string representable.
    
    Since:
    
    MMBase-1.8
  - toString
```
public static String toString(Object o)
```
    Convert an object to a String. null is converted to an empty string.
    
    Parameters:
    
    o - the object to convert
    
    Returns:
    
    the converted value as a String
  - toStringBuffer
```
public static StringBuffer toStringBuffer(StringBuffer buffer,
                                          Object o)
```
    Convert an object to a string, using a StringBuffer.
    
    Parameters:
    
    buffer - The StringBuffer with which to create the string
    
    o - the object to convert
    
    Returns:
    
    the StringBuffer used for conversion (same as the buffer parameter)
    
    Since:
    
    MMBase-1.7
  - toStringBuilder
```
public static StringBuilder toStringBuilder(StringBuilder buffer,
                                            Object o)
```
    Convert an object to a string, using a StringBuilder
    
    Parameters:
    
    buffer - The StringBuilder with which to create the string
    
    o - the object to convert
    
    Returns:
    
    the StringBuilder used for conversion (same as the buffer parameter)
    
    Since:
    
    MMBase-1.9
  - toWriter
```
public static Writer toWriter(Writer writer,
                              Object o)
                       throws IOException
```
    Convert an object to a string, using a Writer.
    
    Parameters:
    
    writer - The Writer with which to create (write) the string
    
    o - the object to convert
    
    Returns:
    
    the Writer used for conversion (same as the writer parameter)
    
    Throws:
    
    IOException
    
    Since:
    
    MMBase-1.7
  - wrap
```
public static Object wrap(Object o,
                          CharTransformer escaper)
```
    Wraps an object in another object with a toString as we desire. Casting can now be done with toString() on the resulting object. This is used to make JSTL en EL behave similarly as mmbase taglib when writing objects to the page (taglib calls Casting, but JSTL of course doesn't).
    
    Parameters:
    
    o - The object to be wrapped
    
    escaper - null or a CharTransformer to pipe the strings through
    
    Since:
    
    MMBase-1.8
    
    To Do:
    
    Not everything is wrapped (and can be unwrapped) already.
  - escape
```
public static String escape(CharTransformer escaper,
                            CharSequence string)
```
  - unWrap
```
public static Object unWrap(Object o)
```
    When you want to undo the wrapping, this method can be used.
    
    Since:
    
    MMBase-1.8
  - toList
```
public static List toList(Object o)
```
    Convert an object to a List. A String is split up (as if it was a comma-separated String). Individual objects are wrapped and returned as Lists with one item. null and the empty string are returned as an empty list.
    
    Parameters:
    
    o - the object to convert
    
    Returns:
    
    the converted value as a List
    
    Since:
    
    MMBase-1.7
  - toList
```
public static List toList(Object o,
                          String delimiter)
```
    As toList(Object) but with one extra argument.
    
    Parameters:
    
    delimiter - Regexp to use when splitting up the string if the object is a String. null or the empty string mean the default, which is a comma.
    
    Since:
    
    MMBase-1.8
  - toMap
```
public static Map toMap(Object o)
```
    Since:
    
    MMBase-1.8
  - toCollection
```
public static Collection toCollection(Object o,
                                      String delimiter)
```
    Transforms an object to a collection. If the object is a collection already, then nothing happens. If it is a Map, then the 'entry set' is returned. A string is interpreted as a comma-separated list of strings. Other objects are wrapped in an ArrayList with one element.
    
    Since:
    
    MMBase-1.8.5
  - toCollection
```
public static Collection toCollection(Object o)
```
    Since:
    
    MMBase-1.8
  - toXML
```
public static Document toXML(Object o)
```
    Convert the value to a Document object. If the value is not itself a Document, the method attempts to attempts to convert the String value into an XML. A null value is returned as null. If the value cannot be converted, this method throws an IllegalArgumentException.
    
    Parameters:
    
    o - the object to be converted to an XML document
    
    Returns:
    
    the value as a DOM Element or null
    
    Throws:
    
    IllegalArgumentException - if the value could not be converted
    
    Since:
    
    MMBase-1.6
  - toByte
```
public static byte[] toByte(Object obj)
```
    Convert an object to a byte array.
    
    Parameters:
    
    obj - The object to be converted
    
    Returns:
    
    the value as an byte[] (binary/blob field)
  - toInputStream
```
public static InputStream toInputStream(Object obj)
```
  - toSerializableInputStream
```
public static SerializableInputStream toSerializableInputStream(Object obj)
```
  - toInt
```
public static int toInt(Object i,
                        int def)
```
    Convert an object to an int. Boolean values return 0 for false, 1 for true. String values are parsed to a number, if possible. If a value is an Node, it's number field is returned. All remaining values return the provided default value.
    
    Parameters:
    
    i - the object to convert
    
    def - the default value if conversion is impossible
    
    Returns:
    
    the converted value as an int
    
    Since:
    
    MMBase-1.7
  - toInt
```
public static int toInt(Object i)
```
    Convert an object to an int. Boolean values return 0 for false, 1 for true. String values are parsed to a number, if possible. If a value is a Node, it's number field is returned. All remaining values return -1.
    
    Parameters:
    
    i - the object to convert
    
    Returns:
    
    the converted value as an int
  - toBoolean
```
public static boolean toBoolean(Object b)
```
    Convert an object to a boolean. If the value is numeric, this call returns true if the value is a positive, non-zero, value. In other words, values '0' and '-1' are considered false. If the value is a string, this call returns true if the value is "true" or "yes" (case-insensitive). In all other cases (including calling byte fields), false is returned.
    
    Parameters:
    
    b - the object to convert
    
    Returns:
    
    the converted value as a boolean
  - toInteger
```
public static Integer toInteger(Object i)
```
    Convert an object to an Integer. Boolean values return 0 for false, 1 for true. String values are parsed to a number, if possible. All remaining values return -1.
    
    Parameters:
    
    i - the object to convert
    
    Returns:
    
    the converted value as a Integer
  - toLong
```
public static long toLong(Object i,
                          long def)
```
    Convert an object to a long. Boolean values return 0 for false, 1 for true. String values are parsed to a number, if possible. All remaining values return the provided default value.
    
    Parameters:
    
    i - the object to convert
    
    def - the default value if conversion is impossible
    
    Returns:
    
    the converted value as a long
    
    Since:
    
    MMBase-1.7
  - toLong
```
public static long toLong(Object i)
```
    Convert an object to a long. Boolean values return 0 for false, 1 for true. String values are parsed to a number, if possible. All remaining values return -1.
    
    Parameters:
    
    i - the object to convert
    
    Returns:
    
    the converted value as a long
    
    Since:
    
    MMBase-1.7
  - toFloat
```
public static float toFloat(Object i,
                            float def)
```
    Convert an object to an float. Boolean values return 0 for false, 1 for true. String values are parsed to a number, if possible. All remaining values return the default value.
    
    Parameters:
    
    i - the object to convert
    
    def - the default value if conversion is impossible
    
    Returns:
    
    the converted value as a float
  - toFloat
```
public static float toFloat(Object i)
```
    Convert an object to an float. Boolean values return 0 for false, 1 for true. String values are parsed to a number, if possible. All remaining values return -1.
    
    Parameters:
    
    i - the object to convert
    
    Returns:
    
    the converted value as a float
  - toDouble
```
public static double toDouble(Object i,
                              double def)
```
    Convert an object to an double. Boolean values return 0 for false, 1 for true. String values are parsed to a number, if possible. All remaining values return the default value.
    
    Parameters:
    
    i - the object to convert
    
    def - the default value if conversion is impossible
    
    Returns:
    
    the converted value as a double
  - toDouble
```
public static double toDouble(Object i)
```
    Convert an object to an double. Boolean values return 0 for false, 1 for true. String values are parsed to a number, if possible. All remaining values return -1.
    
    Parameters:
    
    i - the object to convert
    
    Returns:
    
    the converted value as a double
  - toDecimal
```
public static BigDecimal toDecimal(Object i)
```
    Since:
    
    MMBase-1.9.1
  - toDate
```
public static Date toDate(Object d)
```
    Convert an object to a Date. String values are parsed to a date, if possible. Numeric values are assumed to represent number of seconds since 1970. All remaining values return 1969-12-31 23:59 GMT.
    
    Parameters:
    
    d - the object to convert
    
    Returns:
    
    the converted value as a Date, never null
    
    Since:
    
    MMBase-1.7
  - equals
```
public static boolean equals(Object o1,
                             Object o2)
```
    Since:
    
    MMBase-1.9
  - setHelper
```
public static void setHelper(Caster h)
```
    Since:
    
    MMBase-2.0

Class Casting

Nested Class Summary

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

ISO_8601_LOOSE

ISO_8601_UTC

ISO_8601_DATE

ISO_8601_TIME

DOCUMENTBUILDER

BOOLEAN_PATTERN

DOUBLE_PATTERN

Method Detail

isType

toType

toType

canCast

isStringRepresentable

toString

toStringBuffer

toStringBuilder

toWriter

wrap

escape

unWrap

toList

toList

toMap

toCollection

toCollection

toXML

toByte

toInputStream

toSerializableInputStream

toInt

toInt

toBoolean

toInteger

toLong

toLong

toFloat

toFloat

toDouble

toDouble

toDecimal

toDate

equals

setHelper