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1
7 package java.lang;
8
9 import java.io.*;
10 import java.util.Properties  ;
11 import java.util.PropertyPermission ;
12 import java.util.StringTokenizer ;
13 import java.security.AccessController ;
14 import java.security.PrivilegedAction ;
15 import java.security.AllPermission ;
16 import java.nio.channels.Channel ;
17 import java.nio.channels.spi.SelectorProvider ;
18 import sun.net.InetAddressCachePolicy;
19 import sun.nio.ch.Interruptible;
20 import sun.reflect.Reflection;
21 import sun.security.util.SecurityConstants;
22 import sun.reflect.annotation.AnnotationType;
23
24
38 public final class System {
39
40
41 private static native void registerNatives();
42 static {
43 registerNatives();
44 }
45
46
47 private System() {
48 }
49
50
56 public final static InputStream in = nullInputStream();
57
58
83 public final static PrintStream out = nullPrintStream();
84
85
97 public final static PrintStream err = nullPrintStream();
98
99
101 private static SecurityManager security = null;
102
103
123 public static void setIn(InputStream in) {
124 checkIO();
125 setIn0(in);
126 }
127
128
147 public static void setOut(PrintStream out) {
148 checkIO();
149 setOut0(out);
150 }
151
152
171 public static void setErr(PrintStream err) {
172 checkIO();
173 setErr0(err);
174 }
175
176
177
202 public static Channel inheritedChannel() throws IOException {
203 return SelectorProvider.provider().inheritedChannel();
204 }
205
206 private static void checkIO() {
207 if (security != null)
208 security.checkPermission(new RuntimePermission ("setIO"));
209 }
210
211 private static native void setIn0(InputStream in);
212 private static native void setOut0(PrintStream out);
213 private static native void setErr0(PrintStream err);
214
215
238 public static
239 void setSecurityManager(final SecurityManager s) {
240 try {
241 s.checkPackageAccess("java.lang");
242 } catch (Exception e) {
243 }
245 setSecurityManager0(s);
246 }
247
248 private static synchronized
249 void setSecurityManager0(final SecurityManager s) {
250 if (security != null) {
251 security.checkPermission(new RuntimePermission
254 ("setSecurityManager"));
255 }
256
257 if ((s != null) && (s.getClass().getClassLoader() != null)) {
258 AccessController.doPrivileged(new PrivilegedAction () {
267 public Object run() {
268 s.getClass().getProtectionDomain().implies
269 (SecurityConstants.ALL_PERMISSION);
270 return null;
271 }
272 });
273 }
274
275 security = s;
276 InetAddressCachePolicy.setIfNotSet(InetAddressCachePolicy.FOREVER);
277 }
278
279
287 public static SecurityManager getSecurityManager() {
288 return security;
289 }
290
291
307 public static native long currentTimeMillis();
308
309
334 public static native long nanoTime();
335
336
428 public static native void arraycopy(Object src, int srcPos,
429 Object dest, int destPos,
430 int length);
431
432
443 public static native int identityHashCode(Object x);
444
445
465
466 private static Properties props;
467 private static native Properties initProperties(Properties props);
468
469
559 public static Properties getProperties() {
560 if (security != null) {
561 security.checkPropertiesAccess();
562 }
563 return props;
564 }
565
566
588 public static void setProperties(Properties props) {
589 if (security != null) {
590 security.checkPropertiesAccess();
591 }
592 if (props == null) {
593 props = new Properties ();
594 initProperties(props);
595 }
596 System.props = props;
597 }
598
599
625 public static String getProperty(String key) {
626 checkKey(key);
627 if (security != null) {
628 security.checkPropertyAccess(key);
629 }
630 return props.getProperty(key);
631 }
632
633
659 public static String getProperty(String key, String def) {
660 checkKey(key);
661 if (security != null) {
662 security.checkPropertyAccess(key);
663 }
664 return props.getProperty(key, def);
665 }
666
667
696 public static String setProperty(String key, String value) {
697 checkKey(key);
698 if (security != null)
699 security.checkPermission(new PropertyPermission (key,
700 SecurityConstants.PROPERTY_WRITE_ACTION));
701 return (String ) props.setProperty(key, value);
702 }
703
704
731 public static String clearProperty(String key) {
732 checkKey(key);
733 if (security != null)
734 security.checkPermission(new PropertyPermission (key, "write"));
735 return (String ) props.remove(key);
736 }
737
738 private static void checkKey(String key) {
739 if (key == null) {
740 throw new NullPointerException ("key can't be null");
741 }
742 if (key.equals("")) {
743 throw new IllegalArgumentException ("key can't be empty");
744 }
745 }
746
747
793 public static String getenv(String name) {
794 if (security != null)
795 security.checkPermission(new RuntimePermission ("getenv."+name));
796
797 return ProcessEnvironment.getenv(name);
798 }
799
800
801
841 public static java.util.Map <String ,String > getenv() {
842 if (security != null)
843 security.checkPermission(new RuntimePermission ("getenv.*"));
844
845 return ProcessEnvironment.getenv();
846 }
847
848
868 public static void exit(int status) {
869 Runtime.getRuntime().exit(status);
870 }
871
872
890 public static void gc() {
891 Runtime.getRuntime().gc();
892 }
893
894
912 public static void runFinalization() {
913 Runtime.getRuntime().runFinalization();
914 }
915
916
941 @Deprecated
942 public static void runFinalizersOnExit(boolean value) {
943 Runtime.getRuntime().runFinalizersOnExit(value);
944 }
945
946
967 public static void load(String filename) {
968 Runtime.getRuntime().load0(getCallerClass(), filename);
969 }
970
971
992 public static void loadLibrary(String libname) {
993 Runtime.getRuntime().loadLibrary0(getCallerClass(), libname);
994 }
995
996
1008 public static native String mapLibraryName(String libname);
1009
1010
1016 private static InputStream nullInputStream() throws NullPointerException {
1017 if (currentTimeMillis() > 0)
1018 return null;
1019 throw new NullPointerException ();
1020 }
1021
1022 private static PrintStream nullPrintStream() throws NullPointerException {
1023 if (currentTimeMillis() > 0)
1024 return null;
1025 throw new NullPointerException ();
1026 }
1027
1028
1031 private static void initializeSystemClass() {
1032 props = new Properties ();
1033 initProperties(props);
1034 sun.misc.Version.init();
1035 FileInputStream fdIn = new FileInputStream(FileDescriptor.in);
1036 FileOutputStream fdOut = new FileOutputStream(FileDescriptor.out);
1037 FileOutputStream fdErr = new FileOutputStream(FileDescriptor.err);
1038 setIn0(new BufferedInputStream(fdIn));
1039 setOut0(new PrintStream(new BufferedOutputStream(fdOut, 128), true));
1040 setErr0(new PrintStream(new BufferedOutputStream(fdErr, 128), true));
1041
1042 loadLibrary("zip");
1045
1046 Terminator.setup();
1053
1054 sun.misc.VM.maxDirectMemory();
1058
1059 sun.misc.VM.allowArraySyntax();
1064
1065 sun.misc.VM.booted();
1069
1070 Thread current = Thread.currentThread();
1073 current.getThreadGroup().add(current);
1074
1075 sun.misc.SharedSecrets.setJavaLangAccess(new sun.misc.JavaLangAccess(){
1077 public sun.reflect.ConstantPool getConstantPool(Class klass) {
1078 return klass.getConstantPool();
1079 }
1080 public void setAnnotationType(Class klass, AnnotationType type) {
1081 klass.setAnnotationType(type);
1082 }
1083 public AnnotationType getAnnotationType(Class klass) {
1084 return klass.getAnnotationType();
1085 }
1086 public void blockedOn(Thread t, Interruptible b) {
1087 t.blockedOn(b);
1088 }
1089 });
1090 }
1091
1092
1093 static Class getCallerClass() {
1094 return Reflection.getCallerClass(3);
1096 }
1097}
1098 |
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