Java IO.pdf - Nguyen Dang Binh

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} } StreamCopier.copy(in, out); in.close(); Java I/O The main() method is responsible for choosing the file and format to be dumped. The dump() method translates an input stream onto an output stream using a particular filter. This allows the dump() method to be used by other classes as a more general translation service for streams. An alternative pattern would pass the filter as an argument to dump() rather than an integer mode. This might make the program more flexible but would not allow you to easily chain several filters together as we'll do in upcoming chapters. 95
Chapter 7. Data Streams Java I/O Data streams read and write strings, integers, floating-point numbers, and other data that's commonly presented at a higher level than mere bytes. The java.io.DataInputStream and java.io.DataOutputStream classes read and write the primitive Java data types (boolean, int, double, etc.) and strings in a particular, well-defined, platform-independent format. Since DataInputStream and DataOutputStream use the same formats, they're complementary. What a data output stream writes, a data input stream can read. These classes are especially useful when you need to move data between platforms that may use different native formats for integers or floating-point numbers. 7.1 The Data Stream Classes The java.io.DataInputStream and java.io.DataOutputStream classes are subclasses of FilterInputStream and FilterOutputStream , respectively. public class DataInputStream extends FilterInputStream implements DataInput public class DataOutputStream extends FilterOutputStream implements DataOutput They have all the usual methods you've come to associate with input and output stream classes, such as read(), write(), flush(), available(), skip(), close(), markSupported(), and reset(). (Data input streams support marking if, and only if, their underlying input stream supports marking.) However, the real purpose of DataInputStream and DataOutputStream is not to read and write raw bytes using the standard input and output stream methods. It's to read and interpret multibyte data like ints, floats, doubles, and chars. 7.1.1 The DataInput and DataOutput Interfaces The java.io.DataInput interface declares 15 methods that read various kinds of data: public abstract boolean readBoolean() throws IOException public abstract byte readByte() throws IOException public abstract int readUnsignedByte() throws IOException public abstract short readShort() throws IOException public abstract int readUnsignedShort() throws IOException public abstract char readChar() throws IOException public abstract int readInt() throws IOException public abstract long readLong() throws IOException public abstract float readFloat() throws IOException public abstract double readDouble() throws IOException public abstract String readLine() throws IOException public abstract String readUTF() throws IOException public void readFully(byte[] data) throws IOException public void readFully(byte[] data, int offset, int length) throws IOException public int skipBytes(int n) throws IOException These methods are all available from the DataInputStream class and any other class that implements DataInput. (In the core Java API, this is only DataInputStream and its subclass, ObjectInputStream, which will be discussed in Chapter 11.) Likewise, 96
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Java I/O Elliotte Rusty Harold Publ
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III: Filter Streams ...............
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V: Appendixes .....................
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Preface Java I/O In many ways this
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Java I/O operations from moving byt
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Chapter 9 Chapter 10 Java I/O Chapt
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Chapter 17 Java I/O lining up the d
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Security Issues Java I/O I don't kn
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Java I/O Finally, although many of
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Part I: Basic I/O Java I/O 13
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Java I/O The word stream is derived
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Java I/O The java.util.jar package
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Java I/O For instance, according to
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Java I/O Java understands several d
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Java I/O commonly use an eight-bit
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Java I/O For the most part, these c
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Figure 1.1. An xterm console on Uni
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Java I/O If you absolutely must use
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Java I/O in Apple's Macintosh Runti
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Java I/O to work inside a web brows
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Java I/O bit pattern to a particula
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Java I/O The output is the same as
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OutputStream out = new NullOutputSt
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Figure 2.1. The StreamedTextArea co
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Java I/O When you call read(), you
Page 52 and 53: Java I/O try { byte[] b = new byte[
Page 54 and 55: Java I/O Once you have closed an in
Page 56 and 57: public class StreamCopier { } publi
Page 58 and 59: Chapter 4. File Streams Java I/O Un
Page 60 and 61: } } for (int i = 0; i < args.length
Page 62 and 63: Java I/O The FileOutputStream class
Page 64 and 65: Java I/O ASCII format is the defaul
Page 66 and 67: } } } Java I/O if (hex >= 16) Syste
Page 68 and 69: Java I/O Finally, many HTML files c
Page 70 and 71: Java I/O In particular, URL connect
Page 72 and 73: Java I/O Example 5.3 uses these ste
Page 74 and 75: Java I/O many available ports but o
Page 76 and 77: Java I/O inspecting the port. It kn
Page 78 and 79: } } } String response = "Hello " +
Page 80 and 81: } public void actionPerformed(Actio
Page 82 and 83: Chapter 6. Filter Streams Java I/O
Page 84 and 85: Java I/O output stream, out. Among
Page 86 and 87: Java I/O SourceFile???StringExtract
Page 88 and 89: 6.3 Buffered Streams Java I/O Buffe
Page 90 and 91: public boolean markSupported() Java
Page 92 and 93: The compiler rewrites this complica
Page 94 and 95: public class TeeCopier { } public s
Page 96 and 97: } } try { FileInputStream fin = new
Page 98 and 99: } public int available() throws IOE
Page 100 and 101: public class HexFilter extends Dump
Page 104 and 105: Java I/O the java.io.DataOutput int
Page 106 and 107: Java I/O Although other schemes are
Page 108 and 109: } public static void main(String ar
Page 110 and 111: Java I/O Since Java has no unsigned
Page 112 and 113: dout.close(); } catch (IOException
Page 114 and 115: Java I/O The DataInputStream class
Page 116 and 117: Java I/O The readLine() method read
Page 118 and 119: 7.7 Miscellaneous Methods Java I/O
Page 120 and 121: public synchronized void write(int
Page 122 and 123: ** * Writes a 4 byte Java float to
Page 124 and 125: } * possible that this number is te
Page 126 and 127: */ public byte readByte(int b) thro
Page 128 and 129: } Java I/O long byte4 = in.read();
Page 130 and 131: 7.9 Thread Safety Java I/O The Litt
Page 132 and 133: public static void main(String[] ar
Page 134 and 135: Table 7.2. Command-Line Switches fo
Page 136 and 137: } protected void fill() throws IOEx
Page 138 and 139: Chapter 8. Streams in Memory Java I
Page 140 and 141: UDP Byte array input and output str
Page 142 and 143: } } try { // So that the buffer doe
Page 144 and 145: Java I/O Otherwise, these classes j
Page 146 and 147: } } catch (IOException e) { // prob
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Java I/O The first method fills the
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public class DirectDeflater { } pub
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9.1.2.1 Constructing inflaters Ther
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9.1.2.7 An example Java I/O Example
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Java I/O stream itself, without hav
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Java I/O Each inflater input stream
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Java I/O This writes all remaining
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} } } FileOutputStream fout = new F
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} } } catch (IOException e) {System
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Java I/O Normally, the name argumen
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% java FancyZipLister temp.zip test
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Java I/O All high-order Unicode byt
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Java I/O the files to be stored in
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9.3.3.2 Open the next zip entry Jav
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Java I/O Better checksum schemes us
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} } int b; while ((b = in.read()) !
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Java I/O example, under Unix, to ma
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Java I/O archive. If the signatures
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Java I/O public JarFile(String file
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Java I/O The java.util.jar.Attribut
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9.5.7 Manifest Java I/O What the ja
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public ZipEntry getNextEntry() thro
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Java I/O so throw a java.lang.Unsup
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within the space of the next few li
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Chapter 10. Cryptographic Streams J
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Java I/O • It should be difficult
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Figure 10.1. The four steps to calc
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Java I/O you only want to detect si
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public void reset() Java I/O In pra
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Java I/O After each successful call
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} byte[] result = md.digest(); for
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} } catch (Exception e) {System.err
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public class EasyFileDigest { publi
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Java I/O them your encryption (publ
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Java I/O DES, triple DES (DESede),
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IDEA RC2 RC4 Blowfish Java I/O The
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Figure 10.2. Encrypting data Java I
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} } catch (NoSuchAlgorithmException
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} } Java I/O } catch (InvalidKeySpe
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SecretKey blowfishKey = blowfishKey
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Java I/O public final byte[] doFina
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Java I/O A CipherInputStream object
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10.6.2 CipherOutputStream CipherOut
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} } byte[] newDigest = sha.digest()
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} } else if (args[firstFile].equals
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Java I/O Note how little we had to
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Chapter 11. Object Serialization Ja
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Java I/O To write an object onto a
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Java I/O Needless to say, this is a
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Java I/O java.awt.image.renderable
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Java I/O are not serializable, then
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11.5.1.5 Making nonserializable fie
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Java I/O output streams, but DataIn
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Figure 11.2. The serialver GUI Java
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public SerializableZipFile(File fil
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public class NetworkWindow extends
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private void writeObject(ObjectOutp
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} } Vector v = (Vector) oin.readObj
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Java I/O the resolveClass() method
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Example 11.6. Person import java.ut
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public class SealedPoint { } public
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Chapter 12. Working with Files Java
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Java I/O not begin with an @. Under
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Java I/O placing a minus sign befor
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Java I/O rush to snap up all the go
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System Properties System properties
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Java I/O complete list of the ASCII
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Win32 index.html MacOS index.html N
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Java I/O The path argument should b
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Java I/O assume the array returned
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Example 12.2. Paths import java.io.
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String canonicalPath = f.getCanonic
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Java I/O The isHidden() method, onl
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12.3.4 Manipulating Files Java I/O
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fin.close(); src.delete(); Java I/O
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public int hashCode() public boolea
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public class DirList { } File direc
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12.4 Filename Filters Java I/O You
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} } for (int i = 0; i < htmlFiles.l
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public RandomAccessFile(File file,
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Java I/O • Do not parse pathnames
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Figure 13.2. Motif standard Open di
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Java I/O Example 13.1 is a program
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} } // Work around annoying AWT non
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} // Clean up our windows, they won
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13.2.2 Displaying File Choosers Jav
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13.2.5 Custom Dialogs Java I/O File
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Figure 13.4. The choosable file fil
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Example 13.7. JavaChooser import ja
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13.2.7 Selecting Directories Java I
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public void setFileView(fileView) p
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13.2.12.1 Action events Java I/O Wh
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public TextFilePreview(JFileChooser
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13.3 File Viewer, Part 6 Java I/O W
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} } } theView.setText(""); OutputSt
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} } return deflated.isSelected(); p
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Java I/O Chapter 14. Multilingual C
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Java I/O the upper 128 characters o
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makeBlock("Telugu", 0x0C00, 0x0C7F)
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} } for (int i = 0; i < names.lengt
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14.3 Unicode Escapes Java I/O Curre
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0 0 0 0 0 x10 x9 x8 x7 x6 x5 x4 x3
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Character g = new Character('g'); C
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Java I/O two Latin letters. In uppe
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Java I/O tie, and a few similar cha
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Java I/O The most common type of ch
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Java I/O encoding into a new file c
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Java I/O String openingLineInUnicod
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Java I/O For example, given some Wr
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The flush() and close() methods flu
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15.4 The InputStreamReader Class Th
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Java I/O Similarly, to write text i
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Java I/O These methods behave like
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Java I/O Since string objects are i
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This class has three constructors t
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Do not use the newLine() method if
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Example 15.5. The cat Program impor
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There are four constructors in this
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PipedReader pr = new PipedReader();
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Example 15.7. SourceReader package
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Java I/O question is what to do if
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Java I/O numeric data. If they choo
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} public boolean isText() { if (thi
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default: } } else { LittleEndianInp
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public void init() { } this.addWind
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Chapter 16. Formatted I/O with java
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Java I/O variable salary 12 places
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Hebrew Hebrew Israel iw Hungarian R
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For example: Java I/O NumberFormat
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public void setMaximumIntegerDigits
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Java I/O Like other aspects of text
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Example 16.5. PercentTable import j
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Java I/O align the decimal points i
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Figure 16.1. The PrettiestTable app
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Java I/O This whole class is just a
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Java I/O Most number formats are in
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public int getMultiplier() public v
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Arabic (Saudi Arabia) Arabic (Sudan
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Slovak #,##0.### -1 234,56 #,##0.00
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16.6.2.1 Utility methods Java I/O F
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** * Concrete class for formatting
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} String integerField = digits.subs
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Chapter 17. The Java Communications
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javax.comm.CommPortIdentifier@be4c9
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} } } switch(com.getPortType()) { c
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Java I/O In this example, you see t
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17.2.5 Registering Ports For comple
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} public void run() { } try { byte[
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Java I/O The output buffer size is
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Java I/O Here's the results for bot
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Java I/O If the requested values ar
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Figure 17.1. PC DB-25 serial port t
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public abstract void setRTS(boolean
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Java I/O Steps 1 and 2 should be fa
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Java I/O standard messages on other
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Java I/O serial port events: when t
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17.5.5.3 Step 3 Java I/O In many ci
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Appendix A. Additional Resources Ja
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A.5 Data Compression Java I/O Java
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Java I/O "Developing International
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Appendix B. Character Sets Java I/O
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151 epa (end of guarded area) 183
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Java I/O Cp857 DOS ASCII plus Turki
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Java I/O As extensive as this list
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