java代码实例.docxVIP

第三章--数据类型、变量和表达式：1.public class ByteTest{public static void main ( String [] args ){int a;byte b;a=256;b=(byte)a;System.out.println( b );}}2.public class FloatTest{public static void main ( String [] args ){float f;f = 1.3 ;System.out.println( f );}}3.import javax.swing.JOptionPane;public class ComputeArea{public static void main(String[ ] args){double radius;double area;radius = Double.parseDouble(JOptionPane.showInputDialog(请输入半径值));area = radius * radius *3.14159;JOptionPane.showMessageDialog(null,area = + area);}}第四章—控制：1.// MyInput.java: Contain the methods for reading int, double, and// string values from the keyboardimport java.io.*;public class MyInput{ // Read a string from the keyboard public static String readString() { BufferedReader br = new BufferedReader(new InputStreamReader(System.in), 1); // Declare and initialize the string String string = ; // Get the string from the keyboard try { string = br.readLine(); } catch (IOException ex) { System.out.println(ex); } // Return the string obtained from the keyboard return string; } // Read an int value from the keyboard public static int readInt() { return Integer.parseInt(readString()); } // Read a double value from the keyboard public static double readDouble() { return Double.parseDouble(readString()); } // Read a byte value from the keyboard public static double readByte() { return Byte.parseByte(readString()); } // Read a short value from the keyboard public static double readShort() { return Short.parseShort(readString()); } // Read a long value from the keyboard public static double readLong() { return Long.parseLong(readString()); } // Read a float value from the keyboard public static double readFloat() { return Float.parseFloat(readString()); }}2.import java.io.*;public class LoanCompute{public static void main(String[] args){double loan,ratio,monthlyPay,totalPay;int year;loan=ratio=monthlyPay=totalPay=0;year=0;BufferedReader br= new BufferedReader(new InputStreamReader(System.in), 1);System.out.