处理文本对
Java
应用来说应该算是家常便饭了,在
1.4
出现之前,
Java
自身提供的
API
非常有限,如
String
、
StringTokenizer
、
StringBuffer
,操作也比较单一。无非就是查找
substring
、分解、合并等等。到
1.4
的出现可以说
Java
的文字处理上了一个台阶,因为它支持
regular expression
了。这可是个重量级而方便的东东啊,缺点是太复杂,学习起来有一定难度。相较而言,
Jakarta Commons
提供的
StringUtils
和
WordUtils
至今还维持着那种简洁而强大的美,使用起来也很顺手。来看一个例子:
package
sean.study.jakarta.commons.lang;
import
org.apache.commons.lang.StringUtils;
public
class
StringUtilsAndWordUtilsUsage {
public
static
void
main(String[] args) {
// data setup
String str1 = "";
String str2 = " ";
String str3 = "\t";
String str4 = null;
String str5 = "123";
String str6 = "ABCDEFG";
String str7 = "It feels good to use Jakarta Commons.\r\n";
// check for empty strings
System.out.println("==============================");
System.out.println("Is str1 blank? " + StringUtils.isBlank(str1));
System.out.println("Is str2 blank? " + StringUtils.isBlank(str2));
System.out.println("Is str3 blank? " + StringUtils.isBlank(str3));
System.out.println("Is str4 blank? " + StringUtils.isBlank(str4));
// check for numerics
System.out.println("==============================");
System.out.println("Is str5 numeric? " + StringUtils.isNumeric(str5));
System.out.println("Is str6 numeric? " + StringUtils.isNumeric(str6));
// reverse strings / whole words
System.out.println("==============================");
System.out.println("str6: " + str6);
System.out.println("str6 reversed: " + StringUtils.reverse(str6));
System.out.println("str7: " + str7);
String str8 = StringUtils.chomp(str7);
str8 = StringUtils.reverseDelimited(str8, ' ');
System.out.println("str7 reversed whole words : \r\n" + str8);
// build header (useful to print log messages that are easy to locate)
System.out.println("==============================");
System.out.println("print header:");
String padding = StringUtils.repeat("=", 50);
String msg = StringUtils.center(" Customised Header ", 50, "%");
Object[] raw = new Object[]{padding, msg, padding};
String header = StringUtils.join(raw, "\r\n");
System.out.println(header);
}
}
输出的结果如下:
==============================
Is str1 blank? true
Is str2 blank? true
Is str3 blank? true
Is str4 blank? true
==============================
Is str5 numeric? true
Is str6 numeric? false
==============================
str6: ABCDEFG
str6 reversed: GFEDCBA
str7: It feels good to use Jakarta Commons.
str7 reversed whole words :
Commons. Jakarta use to good feels It
==============================
print header:
==================================================
%%%%%%%%%%%%%%% Customised Header %%%%%%%%%%%%%%%%
==================================================
从代码中我们可以大致了解到这个
StringUtils
类简单而强大的处理能力,从检查空串(对
null
的情况处理很得体),到分割子串,到生成格式化的字符串,使用都很简洁,也很直截了当。
posted @
2007-03-16 22:32 terryliu 阅读(393) |
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