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1,2,3,4,5,6,7,8,9,10,11
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Слайды и текст к этой презентации:
№1 слайд![. Basic I O . Files](/documents_6/eb9d6731d812eb6901b2902324ec9ffc/img0.jpg)
Содержание слайда: 6. Basic I/O
2. Files
№2 слайд![Write to a Text File Example](/documents_6/eb9d6731d812eb6901b2902324ec9ffc/img1.jpg)
Содержание слайда: Write to a Text File Example
import java.io.*;
public void Write(String fileId){
PrintStream outF = null;
try{ outF = new PrintStream(fileId);
outF.println(”This is a test record”); }
catch(IOException e){…processing code }
finally{ if (outF != null) outF.close(); }
}
№3 слайд![Home Exercise Create Deposit](/documents_6/eb9d6731d812eb6901b2902324ec9ffc/img2.jpg)
Содержание слайда: Home Exercise: Create Deposit Report
Modify 512SortDepo project to get deposit report in a text file.
№4 слайд![Read from a Text File Example](/documents_6/eb9d6731d812eb6901b2902324ec9ffc/img3.jpg)
Содержание слайда: Read from a Text File Example
public void Read(String fileId){
BufferedReader inF = null;
try{ inF = new BufferedReader(new FileReader(fileId));
while (txt = inF.readLine() != null){
// code for processing txt
}
}
catch(IOException e) { … processing code }
finally{ if (inF != null) inF.close(); }
}
№5 слайд![Random Access Files Random](/documents_6/eb9d6731d812eb6901b2902324ec9ffc/img4.jpg)
Содержание слайда: Random Access Files
Random access files permit nonsequential, or random, access to a file's contents
To access a file randomly, you:
open the file
seek a particular location
read from or write to that file
№6 слайд![Random Access File Example](/documents_6/eb9d6731d812eb6901b2902324ec9ffc/img5.jpg)
Содержание слайда: Random Access File Example
File f = new File("test.txt");
FileChannel fc = (FileChannel.open(f, READ, WRITE));
fc.position(10);
ByteBuffer copy = ByteBuffer.allocate(12);
do {
nread = fc.read(copy);
// processing copy
}
while (nread != -1 && copy.hasRemaining());
fc.close();
№7 слайд![What Is a Path? Java A file](/documents_6/eb9d6731d812eb6901b2902324ec9ffc/img6.jpg)
Содержание слайда: What Is a Path?
Java 7
A file is identified by its path through the file system, beginning from the root node
The Path class is a programmatic representation of a path in the file system
A Path object contains the file name and directory list used to construct the path
№8 слайд![Relative and Absolute Path A](/documents_6/eb9d6731d812eb6901b2902324ec9ffc/img7.jpg)
Содержание слайда: Relative and Absolute Path
A path is either relative or absolute.
The latter contains the root element.
A relative path needs to be combined with another path in order to access a file.
The character used to separate the directory names (also called the delimiter) is specific to the file system
It is used to examine, locate, and manipulate files
№9 слайд![Creating a Path A Path](/documents_6/eb9d6731d812eb6901b2902324ec9ffc/img8.jpg)
Содержание слайда: Creating a Path
A Path instance contains the information used to specify the location of a file or directory
A root element or a file name might be included, but neither are required
Path p1 = Paths.get("/tmp/foo");
Path p2 = Paths.get(args[0]);
Path p3 = Paths.get(URI.create("file:///Users/joe/FileTest.java"));
№10 слайд![Path Operations Retrieving](/documents_6/eb9d6731d812eb6901b2902324ec9ffc/img9.jpg)
Содержание слайда: Path Operations
Retrieving Information About a Path
Converting a Path
Joining Two Paths
Creating a Path Between Two Paths
Comparing Two Paths
№11 слайд![The File Class The Files](/documents_6/eb9d6731d812eb6901b2902324ec9ffc/img10.jpg)
Содержание слайда: The File Class
The Files class is the other primary entrypoint of the java.nio.file package
You can get some functionality of Path class from the File class in pre-JDK7.
№12 слайд![Some File Operations](/documents_6/eb9d6731d812eb6901b2902324ec9ffc/img11.jpg)
Содержание слайда: Some File Operations
Verifying the Existence of a File or Directory (exists, notExists)
Checking File Accessibility (isReadable, isWritable, isExecutable)
Copying / Moving a File or Directory (copy, move)
Creating and Reading Directories (createDirectory, newDirectoryStream)
№13 слайд![Manuals http docs.oracle.com](/documents_6/eb9d6731d812eb6901b2902324ec9ffc/img12.jpg)
Содержание слайда: Manuals
http://docs.oracle.com/javase/tutorial/essential/io/index.html