要将StringBuilder对象转换为数字,我们可以使用StringBuilder的toString()方法将其转换为String,然后再使用Java提供的解析方法将字符串解析为数字类型。 下面是一个示例代码,演示了如何将一个StringBuilder对象转换为整数类型: StringBuildersb=newStringBuilder();sb.append("12345");intnumber=Integer.parseInt(sb.toString()...
举例:键盘录入"abc"输出结果:"cba"用StringBuffer的功能实现importjava.util.Scanner;publicclassSb2{publicstaticvoidmain(String[] args){Scannersc=newScanner(System.in); String str=sc.nextLine();StringBuffersb=newStringBuffer(str); sb.reverse(); System.out.println(sb); } } StringBuffer和StringBuilde...
public String substring(int start) Java Copy参数: 本方法接受两个参数 start ,它是Integer类型的值,指的是子串的起始索引, end 也是Integer类型的值,指的是子串的结束索引。返回值: 本方法返回位于老序列的索引开始到索引结束的 子串。异常: 如果start或end为负数或大于length(),或者start大于end,该方法会抛出...
其他字母全部小写例如,字符串”i lOvE jAvA”,转换成 “I love java”*/ String s = "i lOvE jAvA"; String first = s.substring(0,1); String other = s.substring(1); System.out.println(first.toUpperCase() + other.toLowerCase
* Some VMs reserve some header words in an array. * Attempts to allocate larger arrays may result in * OutOfMemoryError: Requested array size exceeds VM limit */ private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
/** * Appends the specified string to this character sequence. * * The characters of the {@code String} argument are appended, in * order, increasing the length of this sequence by the length of the * argument. If {@code str} is {@code null}, then the four * characters {@code ...
Returns a string representing the data in this sequence. void trimToSize() Attempts to reduce storage used for the character sequence. Methods inherited from class java.lang.Object clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait Methods inherited from interface ...
1.public class sbbm { 2. 3. static String a; 4. static long time ; 5. public static void main( String[] args ) throws Exception { 6. 7. StringBuilder sb = new StringBuilder(); 8. StringBuilder sb3 = new StringBuilder();
Java中的8种基本数据类型都有与之对应的包装类,如表所示。 表中列举了8种基本数据类型对应的包装类,包装类和基本数据类型进行转换时要涉及两个概念——装箱和拆箱,装箱是指将基本数据类型的值转为引用数据类型的对象,拆箱是指将引用数据类型的对象转为基本数据类型,接下来以int类型的包装类Integer为例来学习装箱和...
package java_practice;public class StringDemo_1 {public static void main(String args[]){String str1 = "jgdabc";String str2 = "jgdabc";System.out.println(str1 == str2);String str3 = new String("jgdabc");String str4 = new String("jgdabc");System.out.println(str2==str3);System.out...