Re: object dumper
"Matt Humphrey" <matth@ivizNOSPAM.com> writes:
"tom arnall" <kloro2006@gmail.com> wrote in message
news:457202cb$0$20558$88260bb3@free.teranews.com...
does anyone know of an object dumper that enables easy output of fields
and
values info to stdout?
I've used the XStream serializer at xstream.codehaus.org Drop in the jar
file and you can get output as easy as
XStream xs = new XStream ();
System.out.println (xs.toXML (yourObject));
I have written a dumper, which dumps to my custom format as the
following example shows:
class Ship
{ Ship ship;
final java.lang.String a0 = "abc";
final java.lang.String a1 = "abc";
final java.lang.String a2 = new java.lang.String( a1 ); }
public class Main
{ public static void main( final java.lang.String[] args )
{ Ship ship = new Ship(); ship.ship = ship; // add self reference
java.lang.System.out.println
( new de.dclj.ram.notation.junobjects.Junobjects().dump( ship )); }}
< &objectmap
object =
< &Ship
a0 =
< &java.lang.String zz0 >
a1 =
< &java.lang.String zz0 >
a2 =
< &java.lang.String zz1 >
ship =
< &Ship object >>
zz0 =
< &java.lang.String
count =
< &int 3 >
hash =
< &int 0 >
offset =
< &int 0 >
value =
< &[char[]] a b c >>
zz1 =
< &java.lang.String
count =
< &int 3 >
hash =
< &int 0 >
offset =
< &int 0 >
value =
< &[char[]] a b c >>>
The dumper is available as part of ram.jar:
http://www.purl.org/stefan_ram/pub/ram-jar
XStream, however, has custom code to handle some special types
of objects, like enums, which Junobjects is missing. The point
is that the value of an enum is not a field of that enum. So,
while Junobjects dumps all the fields, sometimes this is not
what might be wanted.
Another means with only Jave SE is the inbuilt XML Beans encoder:
public class ExampleBean
{ private java.util.Map data;
public ExampleBean(){ data = null; }
public ExampleBean( final java.util.Map value ){ this.data = value; }
public java.util.Map getProperty(){ return data; }
public void setProperty( final java.util.Map value ){ this.data = value; }}
public class Main
{ public static void main( final java.lang.String[] _ )
{ final ExampleBean a = new ExampleBean();
java.util.Map map = new java.util.HashMap();
map.put( "alpha", new java.lang.String[][]{{ "1", "2" },{ "a" }} );
map.put( new java.lang.Integer( 0 ), new java.lang.Double( 1 ));
a.setProperty( map );
final java.beans.XMLEncoder output = new java.beans.XMLEncoder
( new java.io.BufferedOutputStream
( new java.io.FileOutputStream( java.io.FileDescriptor.out )));
try{ output.writeObject( a ); }
finally{ output.close(); }}}
<?xml version="1.0" encoding="UTF-8"?>
<java version="1.6.0" class="java.beans.XMLDecoder">
<object class="ExampleBean">
<void property="property">
<object class="java.util.HashMap">
<void method="put">
<int>0</int>
<double>1.0</double>
</void>
<void method="put">
<string>alpha</string>
<array class="[Ljava.lang.String;" length="2">
<void index="0">
<array class="java.lang.String" length="2">
<void index="0">
<string>1</string>
</void>
<void index="1">
<string>2</string>
</void>
</array>
</void>
<void index="1">
<array class="java.lang.String" length="1">
<void index="0">
<string>a</string>
</void>
</array>
</void>
</array>
</void>
</object>
</void>
</object>
</java>
However, one needs to get used to the behavior of the beans
encoder, too. For example, it will omit fields if they
have their default value as given by the required default
constructor.