javap –verbose class名 查看class文件的具體內容
javap -c class名
繼續看io類
接口 java.io.Closeable
功能:關閉流和相應的資源
java.io.console
功能:使用字節控制臺,與當前的java virtual machine 相關
java.io.DataInput
功能:從二進制流中讀取字節
java.io.DataInputStream
功能:從一個輸入流中讀取原始java數據類型。
public class DataInputStream extends FilterInputStream implements DataInput
java.io.DataOutput
功能:任何java原始類型的數據轉化為字節,將這些字節寫到字節流流中
java.io.DataOutputStream
功能:將原始的java數據類型寫入輸出流中,也可以用datainputstream將數據讀回
java.io.DeleteOnExitHook
功能:持有已經刪除的文件集
java.io.EOFException
功能:指示文件的結尾,或已到達流文件的結尾。
java.io.ExpiringCache
功能:清除過期的實體對象
static class Entry {
private long?? timestamp;
private String val;
Entry(long timestamp, String val) {
this.timestamp = timestamp;
this.val = val;
}
long?? timestamp()????????????????? { return timestamp;?????????? }
void?? setTimestamp(long timestamp) { this.timestamp = timestamp; }
String val()??? ????????????????????{ return val;???????????????? }
void?? setVal(String val)?????????? { this.val = val;???????????? }
}
java.io.Externalizable
功能:只有實現了這個接口的實例才會寫入序列化的流中,負責保存這個實例的內容。
java.io.File
功能:代表抽象的文件和目錄路徑名
By default the classes in the
java.io
package always resolve relative pathnames against the
current user directory.? This directory is named by the system property
user.dir
, and is typically the directory in which the Java
virtual machine was invoked.
static private FileSystem fs = FileSystem.getFileSystem();
file.separator
On UNIX systems the value of this
field is '/'
;
on Microsoft Windows systems it is '\\'
.
public static final char separatorChar = fs.getSeparator();
This character is used to
separate filenames in a sequence of files given as a path list.
On UNIX systems, this character is ':'
; on Microsoft Windows systems it is ';'
.
public static final char pathSeparatorChar = fs.getPathSeparator();
public File(URI uri) {
// Check our many preconditions
if (!uri.isAbsolute())
throw new IllegalArgumentException("URI is not absolute");
if (uri.isOpaque())
throw new IllegalArgumentException("URI is not hierarchical");
String scheme = uri.getScheme();
if ((scheme == null) || !scheme.equalsIgnoreCase("file"))
throw new IllegalArgumentException("URI scheme is not \"file\"");
if (uri.getAuthority() != null)
throw new IllegalArgumentException("URI has an authority component");
if (uri.getFragment() != null)
throw new IllegalArgumentException("URI has a fragment component");
if (uri.getQuery() != null)
throw new IllegalArgumentException("URI has a query component");
String p = uri.getPath();
if (p.equals(""))
throw new IllegalArgumentException("URI path component is empty");
// Okay, now initialize
p = fs.fromURIPath(p);
if (File.separatorChar != '/')
p = p.replace('/', File.separatorChar);
this.path = fs.normalize(p);
this.prefixLength = fs.prefixLength(this.path);
}