int largestinteger= Integer. MAX VALUE, int smallestInteger= Integer. MIN VALUE, long largestLong =Long. MAX VALUE float largestFloat= Float MAX VALUE, double largestDouble= Double. MAX VALUE System. out. printIn(" The largest byte value is"+ largestByte) System. out. printIn( The largest short value is "+ largest Short System. out. println( The largest integer value is"+ largestInteger) System. out println( The smallest integer value is "+ smallestInteger) System. out printIn(" The largest long value is"+ largestLong System. out println( The largest float value is"+ largest Float) System. out. printIn( The largest double value is "+ largestDouble)
int largestInteger = Integer.MAX_VALUE; int smallestInteger = Integer.MIN_VALUE; long largestLong = Long.MAX_VALUE; float largestFloat = Float.MAX_VALUE; double largestDouble = Double.MAX_VALUE; System.out.println("The largest byte value is " + largestByte); System.out.println("The largest short value is " + largestShort); System.out.println("The largest integer value is " + largestInteger); System.out.println("The smallest integer value is " + smallestInteger); System.out.println("The largest long value is " + largestLong); System.out.println("The largest float value is " + largestFloat); System.out.println("The largest double value is " + largestDouble); } }
字符串与各种数据类型之间的转化 public class TransformEXamk public static void main(String args[ D[ ∥字符串与整型之间的转化 Integer a new Integer (1) String s= a. to String; System. out. printIn(s="+s) int i= Integer parseInt( 888 int i2= Integer valueOf( 666"). int Value System. out. printIn(i="+i) System. out. printIn(2="+i2);∥字符串与浮点数之间的转化 Double x= new Double (1.7) String s2=X to String(); System. out. printIn(s2="+S2) double d= Double valueOf( 12.3").double Value() float f= Float. valueOf(-3). float Value( System. out printIn(d="+ d); System. out. printIn(f="+f
字符串与各种数据类型之间的转化 public class TransformExam{ public static void main(String args[ ]) { //字符串与整型之间的转化 Integer a = new Integer(1); String s = a.toString(); System.out.println("s=" + s); int i = Integer.parseInt("888"); int i2 = Integer.valueOf("666").intValue(); System.out.println("i=" + i); System.out.println("i2=" + i2); //字符串与浮点数之间的转化 Double x = new Double(1.7); String s2 = x.toString( ); System.out.println("s2=" + s2); double d = Double.valueOf("12.3").doubleValue( ); float f = Float. valueOf("-.3"). floatValue( ); System.out.println("d=" + d); System.out.println("f=" + f); } }
字符串类和缓冲串类 冷 java. lang包中专门提供了两个类 String String Buffer 来处理字符串,前者用来处理创建之后不会 再做修改和变动的字符串,后者则用来处理 创建之后允许再做修改和变动的字符串。这 两个类共同的特点是都不能再派生子类
字符串类和缓冲串类 ❖ java.lang包中专门提供了两个类 String StringBuffer 来处理字符串，前者用来处理创建之后不会 再做修改和变动的字符串，后者则用来处理 创建之后允许再做修改和变动的字符串。这 两个类共同的特点是都不能再派生子类
String类 冷 String类描述了字符串,所有Java程序中的字 符串字面量,是作为该类的实例来实现的 冷 String类的继承树是 java. lang Object +--java lang String
String类 ❖ String类描述了字符串，所有Java程序中的字 符串字面量，是作为该类的实例来实现的 ❖ String类的继承树是： java.lang.Object | +--java.lang.String
String类提供的构造方法 冷 public String0 .o public String(char chars[) public String(char chars[ l, int startIndex, int numChars %o public String(String value) %o public String(String Buffer buffer)
String类提供的构造方法 ❖ public String (); ❖ public String (char chars[ ]); ❖ public String (char chars[ ],int startIndex,int numChars); ❖ public String(String value) ❖ public String(StringBuffer buffer)