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public class Example05 {

public static void main(String[] args) {

String s = \

System.out.println(\½«×Ö·û´®sÖеÄ×Ö·ûlÌæ»»³Épºó£º\

System.out.println(\½«×Ö·û´®sÖеÄ×Ö·ûllÌæ»»³Éak47ºó£º\ s.replace(\

String ages = \

String[] strArray = ages.split(\

for (int x = 0; x < strArray.length; x++) {

System.out.println(\Êý×éÖеÄË÷ÒýΪ\´¦µÄÖµÊÇ£º\ +strArray[x]);

}

String name = \

System.out.println(\È¥µôÊ×β¿Õ¸ñºóµÄ×Ö·û´®name£º\String s1 = \String s2 = \

System.out.println(\°´ÕÕĬÈÏ×ÖµäµÄ˳Ðò±È½Ï×Ö·û´®s1ºÍs2£º\ s1.compareTo(s2));// 7 } }

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2¡¢compareTo()µÄ·µ»ØÖµÊÇÕûÐÍ£¬ËüÊÇÏȱȽ϶ÔÓ¦×Ö·ûµÄ´óС(ASCIIÂë˳Ðò)¡£Èç¹ûµÚÒ»¸ö×Ö·ûºÍ²ÎÊýµÄµÚÒ»¸ö×Ö·û²»µÈ£¬Ôò½áÊø±È½Ï²¢·µ»ØËûÃÇÖ®¼äµÄ²îÖµ£»Èç¹ûµÚÒ»¸ö×Ö·ûºÍ²ÎÊýµÄµÚÒ»¸ö×Ö·ûÏàµÈ£¬ÔòÒÔµÚ¶þ¸ö×Ö·ûºÍ²ÎÊýµÄµÚ¶þ¸ö×Ö·û×ö±È½Ï£¬ÒÔ´ËÀàÍÆ¡£Ö±ÖÁ±È½ÏµÄ×Ö·û»ò±»±È½ÏµÄ×Ö·ûÓÐÒ»·½È«±È½ÏÍ꣬Õâʱ¾Í±È½Ï×Ö·ûµÄ³¤¶È¡£

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1) ±àдExample06Àà¡£

2) ÔÚmain()·½·¨ÖУ¬Ê¹ÓÃStringBufferÀàÖеķ½·¨£¬ÒÀ´ÎʵÏÖ×Ö·ûÐòÁеÄÌí¼ÓºÍɾ³ý²Ù×÷¡£ 3) ½«Ìí¼ÓºÍɾ³ý²Ù×÷µÄ½á¹ûÊä³ö£¬¸ù¾Ý´òÓ¡½á¹û£¬ÊìϤ¸÷¸ö·½·¨µÄ×÷Óá£

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public class Example06 { }

// ´´½¨¶ÔÏó

StringBuffer sb = new StringBuffer(); System.out.println(\

System.out.println(\µÄÌí¼Ó·½·¨****\

sb.append(100).append(\

System.out.println(\ʹÓÃStringBuffer¶ÔÏóÌí¼ÓÈÎÒâÊý¾ÝÀàÐ͵ÄÊý¾Ýºósb:\+ sb); sb.insert(8, \

System.out.println(\ÔÚsbµÄµÚ9¸öλÖòåÈë'world'×Ö·û´®ºósb:\System.out.println(\µÄɾ³ý·½·¨****\sb.deleteCharAt(1);

System.out.println(\ɾ³ýsbÖеÚ2¸öλÖõÄ×Ö·ûºósb:\sb.delete(5, 10);

System.out.println(\ɾ³ýsbÖеÚ6¸öµ½µÚ11¸ö×Ö·ûºóµÄsb:\}

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2¡¢Ë¼¿¼Ò»Ï£ºStringÀàºÍStringBufferÀàͬÑùÊDzÙ×÷×Ö·û´®µÄÏà¹ØÀ࣬ÄÇôËûÃÇÓÐʲô²»Í¬Ö®´¦ÄØ£¿ a) StringÀà±íʾµÄ×Ö·û´®Êdz£Á¿£¬Ò»µ©´´½¨ºó£¬ÄÚÈݺͳ¤¶È¶¼ÊÇÎÞ·¨¸Ä±äµÄ¡£¶øStringBuffer±íʾ×Ö

·ûÈÝÆ÷£¬ÆäÄÚÈݺͳ¤¶È¶¼¿ÉÒÔËæÊ±Ð޸ġ£ÔÚ²Ù×÷×Ö·û´®Ê±£¬Èç¹û¸Ã×Ö·û´®½öÓÃÓÚ±íʾÊý¾ÝÀàÐÍ£¬ÔòʹÓÃStringÀ༴¿É£¬µ«ÊÇÈç¹ûÐèÒª¶Ô×Ö·û´®ÖеÄ×Ö·û½øÐÐÔöɾ²Ù×÷£¬ÔòʹÓÃStringBufferÀà¡£ b) StringÀา¸ÇÁËObjectÀàµÄequals()·½·¨£¬¶øStringBufferÀàûÓи²¸ÇObjectÀàµÄequals()·½·¨£¬

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String s1 = new String(\String s2 = new String(\

System.out.println(s1.equals(s2)); // ´òÓ¡½á¹ûΪtrue StringBuffer sb1 = new StringBuffer(\StringBuffer sb2 = new StringBuffer(\

System.out.println(sb1.equals(sb2)); // ´òÓ¡½á¹ûΪfalse

c) StringÀà¶ÔÏó¿ÉÒÔÓòÙ×÷·û¡°+¡±½øÐÐÁ¬½Ó£¬¶øStringBufferÀà¶ÔÏóÖ®¼ä²»ÄÜ£¬¾ßÌåʾÀýÈçÏ£º

String s1 = \String s2 = \

String s3 = s1+s2; // ºÏ·¨ System.out.println(s3); // ´òÓ¡Êä³ö ab StringBuffer sb1 = new StringBuffer(\StringBuffer sb2 = new StringBuffer(\

StringBuffer sb3 = sb1+sb2; // ±àÒë³ö´í

°¸Àý6-7 StringBufferÀàµÄÌæ»»¡¢½ØÈ¡ºÍ·´×ª²Ù×÷

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public class Example07{ }

public static void main(String[] args) {

StringBuffer sb = new StringBuffer();

sb.append(\System.out.println(\×·¼Ó×Ö·û´®ºóµÄsb:\

System.out.println(\×Ö·ûÐòÁеÄÌæ»»·½·¨**** \ sb.replace(5, 10, \ÁÖÇàϼ\

System.out.println(\ʹÓÃreplace()·½·¨Ìæ»»ºóµÄsb:\ System.out.println(\×Ö·ûÐòÁеĽØÈ¡·½·¨**** \ String s = sb.substring(5);

System.out.println(\ʹÓÃsubstring()·½·¨½ØÈ¡ºóµÄs:\System.out.println(\

System.out.println(\×Ö·ûÐòÁеķ´×ª·½·¨**** \ sb.reverse();

System.out.println(\ʹÓÃreverse()·½·¨·´×ªºóµÄsb:\ }

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