<b>[java]</b> view plain copy
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("計算字元串中包含某字元數.");
System.out.println(CharSetUtils.count("The quick brown fox jumps over the lazy dog.", "aeiou"));
System.out.println("删除字元串中某字元.");
System.out.println(CharSetUtils.delete("The quick brown fox jumps over the lazy dog.", "aeiou"));
System.out.println("保留字元串中某字元.");
System.out.println(CharSetUtils.keep("The quick brown fox jumps over the lazy dog.", "aeiou"));
System.out.println("合并重複的字元.");
System.out.println(CharSetUtils.squeeze("a bbbbbb c dd", "b d"));
public void objectUtilsDemo() {
System.out.println("**ObjectUtilsDemo**");
System.out.println("Object為null時，預設列印某字元.");
Object obj = null;
System.out.println(ObjectUtils.defaultIfNull(obj, "空"));
System.out.println("驗證兩個引用是否指向的Object是否相等,取決于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("用父類Object的toString()方法傳回對象資訊.");
Date date = new Date();
System.out.println(ObjectUtils.identityToString(date));
System.out.println(date);
System.out.println("傳回類本身的toString()方法結果,對象為null時，傳回0長度字元串.");
System.out.println(ObjectUtils.toString(date));
System.out.println(ObjectUtils.toString(null));
public void serializationUtilsDemo() {
System.out.println("*SerializationUtils**");
byte[] bytes = SerializationUtils.serialize(date);
System.out.println(ArrayUtils.toString(bytes));
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("生成指定長度的随機字元串,好像沒什麼用.");
System.out.println(RandomStringUtils.random(500));
System.out.println("在指定字元串中生成長度為n的随機字元串.");
System.out.println(RandomStringUtils.random(5, "abcdefghijk"));
System.out.println("指定從字元或數字中生成随機字元串.");
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("将字元串重複n次，将文字按某寬度居中，将字元串數組用某字元串連接配接.");
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("縮短到某長度,用...結尾.");
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("傳回兩字元串不同處索引号.");
System.out.println(StringUtils.indexOfDifference("aaabc", "aaacc"));
System.out.println("傳回兩字元串不同處開始至結束.");
System.out.println(StringUtils.difference("aaabcde", "aaaccde"));
System.out.println("截去字元串為以指定字元串結尾的部分.");
System.out.println(StringUtils.chomp("aaabcde", "de"));
System.out.println("檢查一字元串是否為另一字元串的子集.");
System.out.println(StringUtils.containsOnly("aad", "aadd"));
System.out.println("檢查一字元串是否不是另一字元串的子集.");
System.out.println(StringUtils.containsNone("defg", "aadd"));
System.out.println("檢查一字元串是否包含另一字元串.");
System.out.println(StringUtils.contains("defg", "ef"));
System.out.println(StringUtils.containsOnly("ef", "defg"));
System.out.println("傳回可以處理null的toString().");
System.out.println(StringUtils.defaultString("aaaa"));
System.out.println("?" + StringUtils.defaultString(null) + "!");
System.out.println("去除字元中的空格.");
System.out.println(StringUtils.deleteWhitespace("aa bb cc"));
System.out.println("分隔符處理成數組.");
String[] strArray = StringUtils.split("a,b,,c,d,null,e", ",");
System.out.println(strArray.length);
System.out.println(strArray.toString());
System.out.println("判斷是否是某類字元.");
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("獲得系統檔案分隔符.");
System.out.println(SystemUtils.FILE_SEPARATOR);
System.out.println("獲得源檔案編碼.");
System.out.println(SystemUtils.FILE_ENCODING);
System.out.println("獲得ext目錄.");
System.out.println(SystemUtils.JAVA_EXT_DIRS);
System.out.println("獲得java版本.");
System.out.println(SystemUtils.JAVA_VM_VERSION);
System.out.println("獲得java廠商.");
System.out.println(SystemUtils.JAVA_VENDOR);
public void classUtilsDemo() {
System.out.println(genHeader("ClassUtilsDemo"));
System.out.println("擷取類實作的所有接口.");
System.out.println(ClassUtils.getAllInterfaces(Date.class));
System.out.println("擷取類所有父類.");
System.out.println(ClassUtils.getAllSuperclasses(Date.class));
System.out.println("擷取簡單類名.");
System.out.println(ClassUtils.getShortClassName(Date.class));
System.out.println("擷取包名.");
System.out.println(ClassUtils.getPackageName(Date.class));
System.out.println("判斷是否可以轉型.");
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("轉換特殊字元.");
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("字元串轉為數字(不知道有什麼用).");
System.out.println(NumberUtils.toInt("ba", 33));
System.out.println("從數組中選出最大值.");
System.out.println(NumberUtils.max(new int[] { 1, 2, 3, 4 }));
System.out.println("判斷字元串是否全是整數.");
System.out.println(NumberUtils.isDigits("123.1"));
System.out.println("判斷字元串是否是有效數字.");
System.out.println(NumberUtils.isNumber("0123.1"));
public void dateFormatUtilsDemo() {
System.out.println(genHeader("DateFormatUtilsDemo"));
System.out.println("格式化日期輸出.");
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("秒表計時:" + sw.getTime());
private String genHeader(String head) {
header[1] = StringUtils.center(" " + head + " ", 50, "^O^");
return StringUtils.join(header, "\n");
private void validateDemo() {
String[] strarray = { "a", "b", "c" };
System.out.println("驗證功能");
System.out.println(Validate.notEmpty(strarray));
private void wordUtilsDemo() {
System.out.println("單詞處理功能");
String str1 = "wOrD";
String str2 = "ghj\nui\tpo";
System.out.println(WordUtils.capitalize(str1)); // 首字母大寫
System.out.println(WordUtils.capitalizeFully(str1)); // 首字母大寫其它字母小寫
char[] ctrg = { '.' };
System.out.println(WordUtils.capitalizeFully("i aM.fine", ctrg)); // 在規則地方轉換
System.out.println(WordUtils.initials(str1)); // 擷取首字母
System.out.println(WordUtils.initials("Ben John Lee", null)); // 取每個單詞的首字母
char[] ctr = { ' ', '.' };
System.out.println(WordUtils.initials("Ben J.Lee", ctr)); // 按指定規則擷取首字母
System.out.println(WordUtils.swapCase(str1)); // 大小寫逆轉
System.out.println(WordUtils.wrap(str2, 1)); // 解析\n和\t等字元
/**
* @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();
}
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