porqué pasa esto?

[iivo94]

Código Java:

package javaapplication2;
 
import java.io.PrintStream;
 
public class JavaApplication2 {
 
    public static final PrintStream outa=null;
    public static void main(String[] args) {
        System.out.println("ASD");
        JavaApplication2.outa.println("ASDDAS");
    }
}
 

me tira nullpointer exception en la linea donde uso mi nuevo objeto de printstream.
primero intente hacerlo sin poner =null, pero me tirabatambien nullpointerexception, pero enn java tambien esta declarado asi OUT, porque ami no me deja usar mi objeto de printstream pero si me deja usar el objeto out que esta igual declarado que outa? e.e

[LuisChavezB]

Todo objeto necesita ser inicializado antes de ser utilizado, y el objeto out de la clase System también cumple con esta regla.

[iivo94]

netbeans me dice que out esta asi:
public static final printstream out=null;

donde lo inicializa?

[LuisChavezB]

Si verificas el código de la clase System (Openjdk) lo encontraras:
http://grepcode.com/file/repository....stem.java#1087

Código Java:

private static void More ...initializeSystemClass() {
1088        props = new Properties();
1089        initProperties(props);
1090        sun.misc.Version.init();
1091        FileInputStream fdIn = new FileInputStream(FileDescriptor.in);
1092        FileOutputStream fdOut = new FileOutputStream(FileDescriptor.out);
1093        FileOutputStream fdErr = new FileOutputStream(FileDescriptor.err);
1094        setIn0(new BufferedInputStream(fdIn));
1095        setOut0(new PrintStream(new BufferedOutputStream(fdOut, 128), true));
1096        setErr0(new PrintStream(new BufferedOutputStream(fdErr, 128), true));
1097
1098        // Load the zip library now in order to keep java.util.zip.ZipFile
1099        // from trying to use itself to load this library later.
1100        loadLibrary("zip");
1101
1102        // Setup Java signal handlers for HUP, TERM, and INT (where available).
1103        Terminator.setup();
1104
1105        // The order in with the hooks are added here is important as it
1106        // determines the order in which they are run.
1107        // (1)Console restore hook needs to be called first.
1108        // (2)Application hooks must be run before calling deleteOnExitHook.
1109        Shutdown.add(sun.misc.SharedSecrets.getJavaIOAccess().consoleRestoreHook());
1110        Shutdown.add(ApplicationShutdownHooks.hook());
1111        Shutdown.add(sun.misc.SharedSecrets.getJavaIODeleteOnExitAccess());
1112
1113        // Initialize any miscellenous operating system settings that need to be
1114        // set for the class libraries. Currently this is no-op everywhere except
1115        // for Windows where the process-wide error mode is set before the java.io
1116        // classes are used.
1117        sun.misc.VM.initializeOSEnvironment();
1118
1119        // Set the maximum amount of direct memory.  This value is controlled
1120        // by the vm option -XX:MaxDirectMemorySize=<size>.  This method acts
1121        // as an initializer only if it is called before sun.misc.VM.booted().
1122        sun.misc.VM.maxDirectMemory();
1123
1124        // Set a boolean to determine whether ClassLoader.loadClass accepts
1125        // array syntax.  This value is controlled by the system property
1126        // "sun.lang.ClassLoader.allowArraySyntax".  This method acts as
1127        // an initializer only if it is called before sun.misc.VM.booted().
1128        sun.misc.VM.allowArraySyntax();
1129
1130        // Subsystems that are invoked during initialization can invoke
1131        // sun.misc.VM.isBooted() in order to avoid doing things that should
1132        // wait until the application class loader has been set up.
1133        sun.misc.VM.booted();
1134
1135        // The main thread is not added to its thread group in the same
1136        // way as other threads; we must do it ourselves here.
1137        Thread current = Thread.currentThread();
1138        current.getThreadGroup().add(current);
1139
1140        // Allow privileged classes outside of java.lang
1141        sun.misc.SharedSecrets.setJavaLangAccess(new sun.misc.JavaLangAccess(){
1142            public sun.reflect.ConstantPool More ...getConstantPool(Class klass) {
1143                return klass.getConstantPool();
1144            }
1145            public void More ...setAnnotationType(Class klass, AnnotationType type) {
1146                klass.setAnnotationType(type);
1147            }
1148            public AnnotationType More ...getAnnotationType(Class klass) {
1149                return klass.getAnnotationType();
1150            }
1151            public <E extends Enum<E>>
1152                    E[] More ...getEnumConstantsShared(Class<E> klass) {
1153                return klass.getEnumConstantsShared();
1154            }
1155            public void More ...blockedOn(Thread t, Interruptible b) {
1156                t.blockedOn(b);
1157            }
1158        });
1159    }
 

[iivo94]

que es eso de private static initializeSystemclass,

no era que los inicializadores de clase eran un static{} asi seco? eso de arriba es un inicializador de clase? ahgracias me sirvio mucho