Apache Commons Lang包的常用方法总结详解编程语言

import java.io.File; 
import java.io.FileInputStream; 
import java.io.FileNotFoundException; 
import java.io.FileOutputStream; 
import java.io.IOException; 
import java.util.Calendar; 
import java.util.Date; 
import java.util.Iterator; 
  
import org.apache.commons.lang3.ArrayUtils; 
import org.apache.commons.lang3.CharSet; 
import org.apache.commons.lang3.CharSetUtils; 
import org.apache.commons.lang3.ClassUtils; 
import org.apache.commons.lang3.ObjectUtils; 
import org.apache.commons.lang3.RandomStringUtils; 
import org.apache.commons.lang3.SerializationUtils; 
import org.apache.commons.lang3.StringEscapeUtils; 
import org.apache.commons.lang3.StringUtils; 
import org.apache.commons.lang3.SystemUtils; 
import org.apache.commons.lang3.Validate; 
import org.apache.commons.lang3.builder.EqualsBuilder; 
import org.apache.commons.lang3.builder.HashCodeBuilder; 
import org.apache.commons.lang3.builder.ToStringBuilder; 
import org.apache.commons.lang3.builder.ToStringStyle; 
import org.apache.commons.lang3.math.NumberUtils; 
import org.apache.commons.lang3.text.WordUtils; 
import org.apache.commons.lang3.time.DateFormatUtils; 
import org.apache.commons.lang3.time.DateUtils; 
import org.apache.commons.lang3.time.StopWatch; 
  
/*转自霸气的小码农的博客*/ 
public class TestLangDemo { 
  
    public void charSetDemo() { 
        System.out.println ("**CharSetDemo**"); 
        CharSet charSet = CharSet.getInstance ("aeiou"); 
        String demoStr = "The quick brown fox jumps over the lazy dog."; 
        int count = 0; 
        for (int i = 0, len = demoStr.length(); i < len; i++) { 
            if (charSet.contains (demoStr.charAt (i) ) ) { 
                count++; 
            } 
        } 
        System.out.println ("count: " + count); 
    } 
  
    public void charSetUtilsDemo() { 
        System.out.println ("**CharSetUtilsDemo**"); 
        System.out.println ("计算字符串中包含某字符数."); 
        System.out.println (CharSetUtils.count ( 
                                "The quick brown fox jumps over the lazy dog.", "aeiou") ); 
  
        System.out.println ("删除字符串中某字符."); 
        System.out.println (CharSetUtils.delete ( 
                                "The quick brown fox jumps over the lazy dog.", "aeiou") ); 
  
        System.out.println ("保留字符串中某字符."); 
        System.out.println (CharSetUtils.keep ( 
                                "The quick brown fox jumps over the lazy dog.", "aeiou") ); 
  
        System.out.println ("合并重复的字符."); 
        System.out.println (CharSetUtils.squeeze ("a  bbbbbb     c dd", "b d") ); 
    } 
  
    public void objectUtilsDemo() { 
        System.out.println ("**ObjectUtilsDemo**"); 
        System.out.println ("Object为null时，默认打印某字符."); 
        Object obj = null; 
        System.out.println (ObjectUtils.defaultIfNull (obj, "空") ); 
  
        System.out.println ("验证两个引用是否指向的Object是否相等,取决于Object的equals()方法."); 
        Object a = new Object(); 
        Object b = a; 
        Object c = new Object(); 
        System.out.println (ObjectUtils.equals (a, b) ); 
        System.out.println (ObjectUtils.equals (a, c) ); 
  
        System.out.println ("用父类Object的toString()方法返回对象信息."); 
        Date date = new Date(); 
        System.out.println (ObjectUtils.identityToString (date) ); 
        System.out.println (date); 
  
        System.out.println ("返回类本身的toString()方法结果,对象为null时，返回0长度字符串."); 
        System.out.println (ObjectUtils.toString (date) ); 
        System.out.println (ObjectUtils.toString (null) ); 
        System.out.println (date); 
    } 
  
    public void serializationUtilsDemo() { 
        System.out.println ("*SerializationUtils**"); 
        Date date = new Date(); 
        byte[] bytes = SerializationUtils.serialize (date); 
        System.out.println (ArrayUtils.toString (bytes) ); 
        System.out.println (date); 
  
        Date reDate = (Date) SerializationUtils.deserialize (bytes); 
        System.out.println (reDate); 
        System.out.println (ObjectUtils.equals (date, reDate) ); 
        System.out.println (date == reDate); 
  
        FileOutputStream fos = null; 
        FileInputStream fis = null; 
        try { 
            fos = new FileOutputStream (new File ("d:/test.txt") ); 
            fis = new FileInputStream (new File ("d:/test.txt") ); 
            SerializationUtils.serialize (date, fos); 
            Date reDate2 = (Date) SerializationUtils.deserialize (fis); 
  
            System.out.println (date.equals (reDate2) ); 
  
        } catch (FileNotFoundException e) { 
            e.printStackTrace(); 
        } finally { 
            try { 
                fos.close(); 
                fis.close(); 
            } catch (IOException e) { 
                e.printStackTrace(); 
            } 
        } 
  
    } 
  
    public void randomStringUtilsDemo() { 
        System.out.println ("**RandomStringUtilsDemo**"); 
        System.out.println ("生成指定长度的随机字符串,好像没什么用."); 
        System.out.println (RandomStringUtils.random (500) ); 
  
        System.out.println ("在指定字符串中生成长度为n的随机字符串."); 
        System.out.println (RandomStringUtils.random (5, "abcdefghijk") ); 
  
        System.out.println ("指定从字符或数字中生成随机字符串."); 
        System.out.println (RandomStringUtils.random (5, true, false) ); 
        System.out.println (RandomStringUtils.random (5, false, true) ); 
  
    } 
  
    public void stringUtilsDemo() { 
        System.out.println ("**StringUtilsDemo**"); 
        System.out.println ("将字符串重复n次，将文字按某宽度居中，将字符串数组用某字符串连接."); 
        String[] header = new String[3]; 
        header[0] = StringUtils.repeat ("*", 50); 
        header[1] = StringUtils.center ("  StringUtilsDemo  ", 50, "^O^"); 
        header[2] = header[0]; 
        String head = StringUtils.join (header, "/n"); 
        System.out.println (head); 
  
        System.out.println ("缩短到某长度,用...结尾."); 
        System.out.println (StringUtils.abbreviate ( 
                                "The quick brown fox jumps over the lazy dog.", 10) ); 
        System.out.println (StringUtils.abbreviate ( 
                                "The quick brown fox jumps over the lazy dog.", 15, 10) ); 
  
        System.out.println ("返回两字符串不同处索引号."); 
        System.out.println (StringUtils.indexOfDifference ("aaabc", "aaacc") ); 
  
        System.out.println ("返回两字符串不同处开始至结束."); 
        System.out.println (StringUtils.difference ("aaabcde", "aaaccde") ); 
  
        System.out.println ("截去字符串为以指定字符串结尾的部分."); 
        System.out.println (StringUtils.chomp ("aaabcde", "de") ); 
  
        System.out.println ("检查一字符串是否为另一字符串的子集."); 
        System.out.println (StringUtils.containsOnly ("aad", "aadd") ); 
  
        System.out.println ("检查一字符串是否不是另一字符串的子集."); 
        System.out.println (StringUtils.containsNone ("defg", "aadd") ); 
  
        System.out.println ("检查一字符串是否包含另一字符串."); 
        System.out.println (StringUtils.contains ("defg", "ef") ); 
        System.out.println (StringUtils.containsOnly ("ef", "defg") ); 
  
        System.out.println ("返回可以处理null的toString()."); 
        System.out.println (StringUtils.defaultString ("aaaa") ); 
        System.out.println ("?" + StringUtils.defaultString (null) + "!"); 
  
        System.out.println ("去除字符中的空格."); 
        System.out.println (StringUtils.deleteWhitespace ("aa  bb  cc") ); 
  
        System.out.println ("分隔符处理成数组."); 
        String[] strArray = StringUtils.split ("a,b,,c,d,null,e", ","); 
        System.out.println (strArray.length); 
        System.out.println (strArray.toString() ); 
  
        System.out.println ("判断是否是某类字符."); 
        System.out.println (StringUtils.isAlpha ("ab") ); 
        System.out.println (StringUtils.isAlphanumeric ("12") ); 
        System.out.println (StringUtils.isBlank ("") ); 
        System.out.println (StringUtils.isNumeric ("123") ); 
    } 
  
    public void systemUtilsDemo() { 
        System.out.println (genHeader ("SystemUtilsDemo") ); 
        System.out.println ("获得系统文件分隔符."); 
        System.out.println (SystemUtils.FILE_SEPARATOR); 
  
        System.out.println ("获得源文件编码."); 
        System.out.println (SystemUtils.FILE_ENCODING); 
  
        System.out.println ("获得ext目录."); 
        System.out.println (SystemUtils.JAVA_EXT_DIRS); 
  
        System.out.println ("获得java版本."); 
        System.out.println (SystemUtils.JAVA_VM_VERSION); 
  
        System.out.println ("获得java厂商."); 
        System.out.println (SystemUtils.JAVA_VENDOR); 
    } 
  
    public void classUtilsDemo() { 
        System.out.println (genHeader ("ClassUtilsDemo") ); 
        System.out.println ("获取类实现的所有接口."); 
        System.out.println (ClassUtils.getAllInterfaces (Date.class) ); 
  
        System.out.println ("获取类所有父类."); 
        System.out.println (ClassUtils.getAllSuperclasses (Date.class) ); 
  
        System.out.println ("获取简单类名."); 
        System.out.println (ClassUtils.getShortClassName (Date.class) ); 
  
        System.out.println ("获取包名."); 
        System.out.println (ClassUtils.getPackageName (Date.class) ); 
  
        System.out.println ("判断是否可以转型."); 
        System.out.println (ClassUtils.isAssignable (Date.class, Object.class) ); 
        System.out.println (ClassUtils.isAssignable (Object.class, Date.class) ); 
    } 
  
    public void stringEscapeUtilsDemo() { 
        System.out.println (genHeader ("StringEcsapeUtils") ); 
        System.out.println ("转换特殊字符."); 
        System.out.println ("html:" + StringEscapeUtils.escapeHtml3 (" ") ); 
        System.out.println ("html:" + StringEscapeUtils.escapeHtml4 (" ") ); 
        System.out.println ("html:" + StringEscapeUtils.unescapeHtml3 ("<p>") ); 
        System.out.println ("html:" + StringEscapeUtils.unescapeHtml4 ("<p>") ); 
    } 
  
    private final class BuildDemo { 
        String name; 
        int age; 
  
        public BuildDemo (String name, int age) { 
            this.name = name; 
            this.age = age; 
        } 
  
        public String toString() { 
            ToStringBuilder tsb = new ToStringBuilder (this, ToStringStyle.MULTI_LINE_STYLE); 
            tsb.append ("Name", name); 
            tsb.append ("Age", age); 
            return tsb.toString(); 
        } 
  
        public int hashCode() { 
            HashCodeBuilder hcb = new HashCodeBuilder(); 
            hcb.append (name); 
            hcb.append (age); 
            return hcb.hashCode(); 
        } 
  
        public boolean equals (Object obj) { 
            if (! (obj instanceof BuildDemo) ) { 
                return false; 
            } 
            BuildDemo bd = (BuildDemo) obj; 
            EqualsBuilder eb = new EqualsBuilder(); 
            eb.append (name, bd.name); 
            eb.append (age, bd.age); 
            return eb.isEquals(); 
        } 
    } 
  
    public void builderDemo() { 
        System.out.println (genHeader ("BuilderDemo") ); 
        BuildDemo obj1 = new BuildDemo ("a", 1); 
        BuildDemo obj2 = new BuildDemo ("b", 2); 
        BuildDemo obj3 = new BuildDemo ("a", 1); 
  
        System.out.println ("toString()"); 
        System.out.println (obj1); 
        System.out.println (obj2); 
        System.out.println (obj3); 
  
        System.out.println ("hashCode()"); 
        System.out.println (obj1.hashCode() ); 
        System.out.println (obj2.hashCode() ); 
        System.out.println (obj3.hashCode() ); 
  
        System.out.println ("equals()"); 
        System.out.println (obj1.equals (obj2) ); 
        System.out.println (obj1.equals (obj3) ); 
    } 
  
    public void numberUtils() { 
        System.out.println (genHeader ("NumberUtils") ); 
        System.out.println ("字符串转为数字(不知道有什么用)."); 
        System.out.println (NumberUtils.toInt ("ba", 33) ); 
  
        System.out.println ("从数组中选出最大值."); 
        System.out.println (NumberUtils.max (new int[] { 1, 2, 3, 4 }) ); 
  
        System.out.println ("判断字符串是否全是整数."); 
        System.out.println (NumberUtils.isDigits ("123.1") ); 
  
        System.out.println ("判断字符串是否是有效数字."); 
        System.out.println (NumberUtils.isNumber ("0123.1") ); 
    } 
  
    public void dateFormatUtilsDemo() { 
        System.out.println (genHeader ("DateFormatUtilsDemo") ); 
        System.out.println ("格式化日期输出."); 
        System.out.println (DateFormatUtils.format (System.currentTimeMillis(), "yyyy-MM-dd HH:mm:ss") ); 
  
        System.out.println ("秒表."); 
        StopWatch sw = new StopWatch(); 
        sw.start(); 
  
        for (Iterator iterator = DateUtils.iterator (new Date(), DateUtils.RANGE_WEEK_CENTER); iterator.hasNext();) { 
            Calendar cal = (Calendar) iterator.next(); 
            System.out.println (DateFormatUtils.format (cal.getTime(), 
                                "yy-MM-dd HH:mm") ); 
        } 
  
        sw.stop(); 
        System.out.println ("秒表计时:" + sw.getTime() ); 
  
    } 
  
    private String genHeader (String head) { 
        String[] header = new String[3]; 
        header[0] = StringUtils.repeat ("*", 50); 
        header[1] = StringUtils.center ("  " + head + "  ", 50, "^O^"); 
        header[2] = header[0]; 
        return StringUtils.join (header, "/n"); 
    } 
  
    private void validateDemo() { 
        String[] strarray = {"a", "b", "c"}; 
        System.out.println ("验证功能"); 
        System.out.println (Validate.notEmpty (strarray) ); 
    } 
  
    private void wordUtilsDemo() { 
        System.out.println ("单词处理功能"); 
        String str1 = "wOrD"; 
        String str2 = "ghj/nui/tpo"; 
        System.out.println (WordUtils.capitalize (str1) ); //首字母大写 
        System.out.println (WordUtils.capitalizeFully (str1) ); //首字母大写其它字母小写 
        char[] ctrg = {'.'}; 
        System.out.println (WordUtils.capitalizeFully ("i aM.fine", ctrg) ); //在规则地方转换 
        System.out.println (WordUtils.initials (str1) ); //获取首字母 
        System.out.println (WordUtils.initials ("Ben John Lee", null) ); //取每个单词的首字母 
        char[] ctr = {' ', '.'}; 
        System.out.println (WordUtils.initials ("Ben J.Lee", ctr) ); //按指定规则获取首字母 
        System.out.println (WordUtils.swapCase (str1) ); //大小写逆转 
        System.out.println (WordUtils.wrap (str2, 1) ); //解析/n和/t等字符 
    } 
  
    /** 
     * @param args 
     */ 
    public static void main (String[] args) { 
        TestLangDemo langDemo = new TestLangDemo(); 
  
        langDemo.charSetDemo(); 
        langDemo.charSetUtilsDemo(); 
        langDemo.objectUtilsDemo(); 
        langDemo.serializationUtilsDemo(); 
        langDemo.randomStringUtilsDemo(); 
        langDemo.stringUtilsDemo(); 
        langDemo.systemUtilsDemo(); 
        langDemo.classUtilsDemo(); 
        langDemo.stringEscapeUtilsDemo(); 
        langDemo.builderDemo(); 
        langDemo.numberUtils(); 
        langDemo.dateFormatUtilsDemo(); 
        langDemo.validateDemo(); 
        langDemo.wordUtilsDemo(); 
    } 
  
}