Java by API/java.util/Scanner — различия между версиями
Admin (обсуждение | вклад) м (1 версия) |
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(нет различий)
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Версия 20:43, 31 мая 2010
Содержание
- 1 new Scanner(FileReader file)
- 2 new Scanner(InputStream source)
- 3 new Scanner(Readable source)
- 4 new Scanner(String instr)
- 5 Scanner: findInLine(String str)
- 6 Scanner: findWithinHorizon(String pattern, int horizon)
- 7 Scanner: hasNext()
- 8 Scanner: hasNextBoolean()
- 9 Scanner: hasNextDouble()
- 10 Scanner: hasNextInt()
- 11 Scanner: hasNextLine()
- 12 Scanner: next()
- 13 Scanner: nextBoolean()
- 14 Scanner: nextDouble()
- 15 Scanner: nextInt()
- 16 Scanner: nextLine()
- 17 Scanner: useDelimiter(String pattern)
new Scanner(FileReader file)
<source lang="java">
/**
*Output:
String: Testing String: Scanner int: 10 double: 12.2 String: one boolean: true String: two boolean: false
*/
import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.util.Scanner; public class MainClass {
public static void main(String args[]) throws IOException { int i; double d; boolean b; String str; FileWriter fout = new FileWriter("test.txt"); fout.write("Testing Scanner 10 12.2 one true two false"); fout.close(); FileReader fin = new FileReader("Test.txt"); Scanner src = new Scanner(fin); while (src.hasNext()) { if (src.hasNextInt()) { i = src.nextInt(); System.out.println("int: " + i); } else if (src.hasNextDouble()) { d = src.nextDouble(); System.out.println("double: " + d); } else if (src.hasNextBoolean()) { b = src.nextBoolean(); System.out.println("boolean: " + b); } else { str = src.next(); System.out.println("String: " + str); } } fin.close(); }
}
</source>
new Scanner(InputStream source)
<source lang="java">
/**
*Output: */
import java.util.Scanner; public class MainClass {
public static void main(String args[]) { Scanner conin = new Scanner(System.in); int count = 0; double sum = 0.0; System.out.println("Enter numbers to average."); while (conin.hasNext()) { if (conin.hasNextDouble()) { sum += conin.nextDouble(); count++; } else { String str = conin.next(); if (str.equals("done")) break; else { System.out.println("Data format error."); return; } } } System.out.println("Average is " + sum / count); }
}
</source>
new Scanner(Readable source)
<source lang="java">
/*
*/
import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.util.Scanner; public class MainClass {
public static void main(String args[]) throws IOException { int count = 0; double sum = 0.0; FileWriter fout = new FileWriter("test.txt"); fout.write("2, 3.4, 5,6, 7.4, 9.1, 10.5, done"); fout.close(); FileReader fin = new FileReader("Test.txt"); Scanner src = new Scanner(fin); src.useDelimiter(", *"); while(src.hasNext()) { if(src.hasNextDouble()) { sum += src.nextDouble(); count++; } else { String str = src.next(); if(str.equals("done")) break; else { System.out.println("File format error."); return; } } } fin.close(); System.out.println("Average is " + sum / count); }
}
</source>
new Scanner(String instr)
<source lang="java">
/**
*Output:
28
*/
import java.util.Scanner; public class MainClass {
public static void main(String args[]) { String instr = "Name: Joe Age: 28 ID: 77"; Scanner conin = new Scanner(instr); conin.findInLine("Age:"); // find Age if (conin.hasNext()) System.out.println(conin.next()); else System.out.println("Error!"); }
}
</source>
Scanner: findInLine(String str)
<source lang="java">
/**
*Output:
28
*/
import java.util.Scanner; public class MainClass {
public static void main(String args[]) { String instr = "Name: Joe Age: 28 ID: 77"; Scanner conin = new Scanner(instr); conin.findInLine("Age:"); // find Age if (conin.hasNext()) System.out.println(conin.next()); else System.out.println("Error!"); }
}
</source>
Scanner: findWithinHorizon(String pattern, int horizon)
<source lang="java">
import java.util.Scanner; public class Main {
public static void main(String args[]) { Scanner sc = new Scanner("Name: Tom Age: 28 ID: 77"); sc.findWithinHorizon("ID:",100); if (sc.hasNext()) System.out.println(sc.next()); else System.out.println("Error!"); }
}
</source>
Scanner: hasNext()
<source lang="java">
/**
*Output: */
import java.util.Scanner; public class MainClass {
public static void main(String args[]) { Scanner conin = new Scanner(System.in); int count = 0; double sum = 0.0; System.out.println("Enter numbers to average."); while (conin.hasNext()) { if (conin.hasNextDouble()) { sum += conin.nextDouble(); count++; } else { String str = conin.next(); if (str.equals("done")) break; else { System.out.println("Data format error."); return; } } } System.out.println("Average is " + sum / count); }
}
</source>
Scanner: hasNextBoolean()
<source lang="java">
/* String: string boolean: true boolean: false int: 1 int: 2 int: 3 double: 4.12
*/
import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.util.Scanner; public class MainClass {
public static void main(String args[]) throws IOException { int i; double d; boolean b; String str; FileWriter fout = new FileWriter("test.txt"); fout.write("string true false 1 2 3 4.12"); fout.close(); FileReader fin = new FileReader("Test.txt"); Scanner src = new Scanner(fin); while (src.hasNext()) { if (src.hasNextInt()) { i = src.nextInt(); System.out.println("int: " + i); } else if (src.hasNextDouble()) { d = src.nextDouble(); System.out.println("double: " + d); } else if (src.hasNextBoolean()) { b = src.nextBoolean(); System.out.println("boolean: " + b); } else { str = src.next(); System.out.println("String: " + str); } } fin.close(); }
}
</source>
Scanner: hasNextDouble()
<source lang="java">
/**
*Output: */
import java.util.Scanner; public class MainClass {
public static void main(String args[]) { Scanner conin = new Scanner(System.in); int count = 0; double sum = 0.0; System.out.println("Enter numbers to average."); while (conin.hasNext()) { if (conin.hasNextDouble()) { sum += conin.nextDouble(); count++; } else { String str = conin.next(); if (str.equals("done")) break; else { System.out.println("Data format error."); return; } } } System.out.println("Average is " + sum / count); }
}
</source>
Scanner: hasNextInt()
<source lang="java">
/* String: string boolean: true boolean: false int: 1 int: 2 int: 3 double: 4.12
*/
import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.util.Scanner; public class MainClass {
public static void main(String args[]) throws IOException { int i; double d; boolean b; String str; FileWriter fout = new FileWriter("test.txt"); fout.write("string true false 1 2 3 4.12"); fout.close(); FileReader fin = new FileReader("Test.txt"); Scanner src = new Scanner(fin); while (src.hasNext()) { if (src.hasNextInt()) { i = src.nextInt(); System.out.println("int: " + i); } else if (src.hasNextDouble()) { d = src.nextDouble(); System.out.println("double: " + d); } else if (src.hasNextBoolean()) { b = src.nextBoolean(); System.out.println("boolean: " + b); } else { str = src.next(); System.out.println("String: " + str); } } fin.close(); }
}
</source>
Scanner: hasNextLine()
<source lang="java">
import java.io.File; import java.util.Scanner; public class Main {
public static void main(String[] args) throws Exception{ File file = new File("data.txt"); Scanner scanner = new Scanner(file); while (scanner.hasNextLine()) { String line = scanner.nextLine(); System.out.println(line); } }
}
</source>
Scanner: next()
<source lang="java">
/**
*Output: */
import java.util.Scanner; public class MainClass {
public static void main(String args[]) { Scanner conin = new Scanner(System.in); int count = 0; double sum = 0.0; System.out.println("Enter numbers to average."); while (conin.hasNext()) { if (conin.hasNextDouble()) { sum += conin.nextDouble(); count++; } else { String str = conin.next(); if (str.equals("done")) break; else { System.out.println("Data format error."); return; } } } System.out.println("Average is " + sum / count); }
}
</source>
Scanner: nextBoolean()
<source lang="java">
/* String: string boolean: true boolean: false int: 1 int: 2 int: 3 double: 4.12
*/
import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.util.Scanner; public class MainClass {
public static void main(String args[]) throws IOException { int i; double d; boolean b; String str; FileWriter fout = new FileWriter("test.txt"); fout.write("string true false 1 2 3 4.12"); fout.close(); FileReader fin = new FileReader("Test.txt"); Scanner src = new Scanner(fin); while (src.hasNext()) { if (src.hasNextInt()) { i = src.nextInt(); System.out.println("int: " + i); } else if (src.hasNextDouble()) { d = src.nextDouble(); System.out.println("double: " + d); } else if (src.hasNextBoolean()) { b = src.nextBoolean(); System.out.println("boolean: " + b); } else { str = src.next(); System.out.println("String: " + str); } } fin.close(); }
}
</source>
Scanner: nextDouble()
<source lang="java">
/* String: string boolean: true boolean: false int: 1 int: 2 int: 3 double: 4.12
*/
import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.util.Scanner; public class MainClass {
public static void main(String args[]) throws IOException { int i; double d; boolean b; String str; FileWriter fout = new FileWriter("test.txt"); fout.write("string true false 1 2 3 4.12"); fout.close(); FileReader fin = new FileReader("Test.txt"); Scanner src = new Scanner(fin); while (src.hasNext()) { if (src.hasNextInt()) { i = src.nextInt(); System.out.println("int: " + i); } else if (src.hasNextDouble()) { d = src.nextDouble(); System.out.println("double: " + d); } else if (src.hasNextBoolean()) { b = src.nextBoolean(); System.out.println("boolean: " + b); } else { str = src.next(); System.out.println("String: " + str); } } fin.close(); }
}
</source>
Scanner: nextInt()
<source lang="java">
/* String: string boolean: true boolean: false int: 1 int: 2 int: 3 double: 4.12
*/
import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.util.Scanner; public class MainClass {
public static void main(String args[]) throws IOException { int i; double d; boolean b; String str; FileWriter fout = new FileWriter("test.txt"); fout.write("string true false 1 2 3 4.12"); fout.close(); FileReader fin = new FileReader("Test.txt"); Scanner src = new Scanner(fin); while (src.hasNext()) { if (src.hasNextInt()) { i = src.nextInt(); System.out.println("int: " + i); } else if (src.hasNextDouble()) { d = src.nextDouble(); System.out.println("double: " + d); } else if (src.hasNextBoolean()) { b = src.nextBoolean(); System.out.println("boolean: " + b); } else { str = src.next(); System.out.println("String: " + str); } } fin.close(); }
}
</source>
Scanner: nextLine()
<source lang="java">
import java.io.File; import java.util.Scanner; public class Main {
public static void main(String[] args) throws Exception{ File file = new File("data.txt"); Scanner scanner = new Scanner(file); while (scanner.hasNextLine()) { String line = scanner.nextLine(); System.out.println(line); } }
}
</source>
Scanner: useDelimiter(String pattern)
<source lang="java">
/*
*/
import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.util.Scanner; public class MainClass {
public static void main(String args[]) throws IOException { int count = 0; double sum = 0.0; FileWriter fout = new FileWriter("test.txt"); fout.write("2, 3.4, 5,6, 7.4, 9.1, 10.5, done"); fout.close(); FileReader fin = new FileReader("Test.txt"); Scanner src = new Scanner(fin); src.useDelimiter(", *"); while(src.hasNext()) { if(src.hasNextDouble()) { sum += src.nextDouble(); count++; } else { String str = src.next(); if(str.equals("done")) break; else { System.out.println("File format error."); return; } } } fin.close(); System.out.println("Average is " + sum / count); }
}
</source>