Class System java.lang.Object | +--java.lang.System public static final PrintStream "out":The "standard" output stream. This stream is already open and ready to accept output data. Typically this stream corresponds to display output or another output destination specified by the host environment or user.
System.out表明out是System类下的一个实例（是一个static variale） 它的定义是：public static final PrintStream out print()是PrintStream的一个method。
public final class System extends Object This Class provides a system-independent interface to system functionality. One of the more useful things provided by this Class are the standard input and output streams. The standard input streams are used for reading character data. The standard output streams are used for printing. For example: System.out.println("Hello World!");
This Class cannot be instantiated or subclassed because all of the methods and variables are static. --------------------------------------------------------------------- method : out public static PrintStream out
Standard output stream. This stream is used for printing messages. --------------------------------------------------------------------------- Class java.io.PrintStream java.lang.Object | +----java.io.OutputStream | +----java.io.FilterOutputStream | +----java.io.PrintStream
public class PrintStream extends FilterOutputStream This class implements an output stream that has additional methods for printing. You can specify that the stream should be flushed every time a newline character is written. The top byte of 16 bit characters is discarded. Example: System.out.println("Hello world!"); System.out.print("x = "); System.out.println(x); System.out.println("y = " + y);
out-输出设备
in-输入设备
|
+--java.lang.System
public static final PrintStream "out":The "standard" output stream. This stream is already open and ready to accept output data. Typically this stream corresponds to display output or another output destination specified by the host environment or user.
它的定义是：public static final PrintStream out
print()是PrintStream的一个method。
|
+----java.lang.System
______________________________________________________________________________
public final class System
extends Object This Class provides a system-independent interface to system functionality. One of the more useful things provided by this Class are the standard input and output streams. The standard input streams are used for reading character data. The standard output streams are used for printing. For example: System.out.println("Hello World!");
This Class cannot be instantiated or subclassed because all of the methods and variables are static. ---------------------------------------------------------------------
method :
out public static PrintStream out
Standard output stream. This stream is used for printing messages.
---------------------------------------------------------------------------
Class java.io.PrintStream java.lang.Object
|
+----java.io.OutputStream
|
+----java.io.FilterOutputStream
|
+----java.io.PrintStream
______________________________________________________________________________
public class PrintStream
extends FilterOutputStream This class implements an output stream that has additional methods for printing. You can specify that the stream should be flushed every time a newline character is written.
The top byte of 16 bit characters is discarded. Example: System.out.println("Hello world!");
System.out.print("x = ");
System.out.println(x);
System.out.println("y = " + y);
______________________________________________________________________________
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