자바 상용 도구 클래스 집합 예시 코드
private static void fileUtilsTest() {
try {
//
String readFileToString = FileUtils.readFileToString(new File("D:\\guor\\data\\test20211022000000.txt"));
System.out.println(readFileToString);
//
FileUtils.deleteDirectory(new File("D:\\guor1\\data1"));
FileUtils.deleteQuietly(new File("D:\\guor\\data"));
//
FileUtils.cleanDirectory(new File("D:\\guor\\data"));
//
boolean contentEquals = FileUtils.contentEquals(new File("D:\\guor\\data\\test20211022000000.txt"), new File("D:\\guor\\data\\testNew20211021000000.txt"));
boolean contentEquals2 = FileUtils.contentEquals(new File("D:\\guor\\data\\ 20211021100000.txt"), new File("D:\\guor\\data\\ New20211022100000.txt"));
System.out.println(contentEquals+","+contentEquals2);
//
FileUtils.copyDirectory(new File("D:\\guor\\data"), new File("D:\\guor\\data2"), new FileFilter() {
@Override
public boolean accept(File pathname) {
if(pathname.getName().startsWith("test")) {
return true;
}
return false;
}
});
FileUtils.moveDirectory(new File("D:\\guor\\data"), new File("D:\\guor\\data3"));
FileUtils.moveFileToDirectory(new File("D:\\guor\\data"), new File("D:\\guor\\data3"), true);
FileUtils.moveToDirectory(new File("D:\\guor\\data"), new File("D:\\guor\\data4"), true);
boolean directoryContains = FileUtils.directoryContains(new File("D:\\guor\\data"), new File("D:\\guor\\data\\test20211022000000.txt"));
System.out.println(directoryContains);
directoryContains = FileUtils.directoryContains(new File("D:\\guor\\data"), new File("*.txt"));
System.out.println(directoryContains);
//
File[] listFiles = new File("D:\\guor\\data").listFiles(new FilenameFilter() {
@Override
public boolean accept(File dir, String name) {
return name.startsWith("test");
}
});
System.out.println(Arrays.toString(listFiles));
// temp
File tempDirectory = FileUtils.getTempDirectory();
System.out.println(tempDirectory);
//
File userDirectory = FileUtils.getUserDirectory();
System.out.println(userDirectory);
//
SimpleDateFormat sdf =new SimpleDateFormat("yyyyMMddHHmmss" );
Date parse = sdf.parse("20210206134900");
boolean fileNewer = FileUtils.isFileNewer(new File("D:\\guor\\data"), parse);
System.out.println(fileNewer);
// ， ， ；
FileUtils.touch(new File("D:\\guor\\data\\test20211022000000.txt"));
//
boolean waitFor = FileUtils.waitFor(new File("D:\\guor\\data\\testNew20211021000000.txt"), 5);
System.out.println(waitFor);
} catch (Exception e) {
System.out.println(e);
}
}
//
public static void test02() {
String dir = "D:\\data";
File[] listFiles = new File(dir).listFiles();
List<File> asList = Arrays.asList(listFiles);
for(File file:listFiles) {
System.out.println(file);
}
Collections.sort(asList, new Comparator<File>() {
@Override
public int compare(File o1, File o2) {
if(o1.lastModified()<o2.lastModified()) {
return -1;
}else if(o1.lastModified()>o2.lastModified()) {
return 1;
}else {
return 0;
}
}
});
System.out.println("sort...");
for(File file:listFiles) {
System.out.println(file+","+file.lastModified());
}
}
private static void stringUtilsTest() {
String str = "hello world";
//
String capitalize = StringUtils.capitalize(str);
System.out.println(capitalize);//Hello
//
String center = StringUtils.center(str, 7);
System.out.println(center);// hello
String center = StringUtils.center(str, 7, "*");
System.out.println(center);//*hello*
//chomp
\r\ \r
String chomp = StringUtils.chomp(str);
System.out.println(chomp);
//chop （
\r\ \r
）
String chop = StringUtils.chop(str);
System.out.println(chop);//hello worl
//
boolean containsAny = StringUtils.containsAny(str, "W");
System.out.println(containsAny);
// ，
containsAny = StringUtils.containsIgnoreCase(str, "W");
System.out.println(containsAny);
//
int indexOfAnyBut = StringUtils.indexOfAnyBut(str, "hello orld");
System.out.println(indexOfAnyBut);
//
int indexOfDifference = StringUtils.indexOfDifference(str, str);
System.out.println(indexOfDifference);
indexOfDifference = StringUtils.indexOfDifference(str, str+"zs");
System.out.println(indexOfDifference);
indexOfDifference = StringUtils.indexOfDifference(str, "he llo");
System.out.println(indexOfDifference);
//
boolean isNumeric = StringUtils.isNumeric(str);
System.out.println(isNumeric);//false
isNumeric = StringUtils.isNumeric("1234dd");
System.out.println("1234dd:"+isNumeric);//false
isNumeric = StringUtils.isNumeric("1234 ");
System.out.println("1234 :"+isNumeric);//false
isNumeric = StringUtils.isNumeric("1.234");
System.out.println("1.234:"+isNumeric);//false
isNumeric = StringUtils.isNumeric("1234");
System.out.println("1234:" + isNumeric);//true
isNumeric = StringUtils.isNumeric("-1234");
System.out.println("-1234:" + isNumeric);//false
//
boolean isNumeric = StringUtils.isNumericSpace(str);
// ，
Object[] array = new Object[] {"zs",18," ",666,777};
String join = StringUtils.join(array);
System.out.println(Arrays.toString(array));
join = StringUtils.join(array, "*");
System.out.println(join);
Object[] array = new Object[] {"zs",18," ",666,777};
String join = StringUtils.join(array, ";", 2, 5);
System.out.println(join);
String remove = StringUtils.remove(str, "hello");
System.out.println(remove);// world
String repeat = StringUtils.repeat(str, 3);
System.out.println(repeat);//hello worldhello worldhello world
repeat = StringUtils.repeat(str, ",", 3);
System.out.println(repeat);//hello world,hello world,hello world
//
String[] list = new String[] {"hello", "girl"};
String[] replacementList = new String[] {"say", "woman"};
String str2 = "hello world,hello boy,hello girl.";
String replaceEach = StringUtils.replaceEach(str2, list, replacementList);
System.out.println(replaceEach);//say world,say boy,say woman.
//
String replaceOnce = StringUtils.replaceOnce("hello world,hello boy,hello girl.", "hello", "say");
System.out.println(replaceOnce);//say world,hello boy,hello girl.
//
String substringAfterLast = StringUtils.substringAfterLast("hello world,hello boy,hello girl.", " ");
System.out.println(substringAfterLast);//girl.
String substringBeforeLast = StringUtils.substringBeforeLast("hello world,hello boy,hello girl.", " ");
System.out.println(substringBeforeLast);//hello world,hello boy,hello
}
private static void collectionUtilsTest() {
List<String> list = new ArrayList<String>();
list.add("zhangsan");
list.add("dalian");
list.add("gateway");
list.add("gateway");
list.add("28");
list.add("35");
//
Object find = CollectionUtils.find(list, new Predicate() {
@Override
public boolean evaluate(Object arg0) {
if(StringUtils.isNumeric(arg0.toString())) {
return false;
}
return true;
}
});
//
Collection select = CollectionUtils.select(list, new Predicate() {
@Override
public boolean evaluate(Object arg0) {
if(StringUtils.isNumeric(arg0.toString())) {
return false;
}
return true;
}
});
System.out.println(list);//[zhangsan, dalian, 28]
System.out.println(find);//zhangsan
System.out.println(select);//[zhangsan, dalian]
List<String> list2 = new ArrayList<String>();
list2.add("zhangsan");
list2.add("dalian2");
list2.add("282");
//
boolean containsAny = CollectionUtils.containsAny(list, list2);
System.out.println(containsAny);//true
//
int countMatches = CollectionUtils.countMatches(list, new Predicate() {
@Override
public boolean evaluate(Object arg0) {
if(StringUtils.isNumeric(arg0.toString())) {
return true;
}
return false;
}
});
System.out.println(countMatches);
//
boolean exists = CollectionUtils.exists(list, new Predicate() {
@Override
public boolean evaluate(Object arg0) {
if(StringUtils.isNumeric(arg0.toString())) {
return true;
}
return false;
}
});
System.out.println(exists);
//
System.out.println(list);//[zhangsan, dalian, , 28, 35]
CollectionUtils.filter(list, new Predicate() {
@Override
public boolean evaluate(Object arg0) {
if(StringUtils.isNumeric(arg0.toString())) {
return false;
}
return true;
}
});
System.out.println(list);//[zhangsan, dalian, ]
//
Object find = CollectionUtils.find(list, new Predicate() {
@Override
public boolean evaluate(Object arg0) {
if(StringUtils.isNumeric(arg0.toString())) {
return false;
}
return true;
}
});
System.out.println(find);//zhangsan
//
System.out.println(list);
CollectionUtils.forAllDo(list, new Closure() {
@Override
public void execute(Object arg0) {
if(StringUtils.isNumeric(arg0.toString())) {
work(arg0);
}
}
});
System.out.println(list);
//
System.out.println(list);//[zhangsan, dalian, gateway, gateway, 28, 35]
Map cardinalityMap = CollectionUtils.getCardinalityMap(list);
System.out.println(cardinalityMap);//{35=1, 28=1, zhangsan=1, dalian=1, gateway=2}
//
List<String> list2 = new ArrayList<String>();
list2.add("lisi");
list2.add("beijing");
list2.add("gateway");
list.add("19");
Collection intersection = CollectionUtils.intersection(list, list2);
System.out.println(intersection);
// List<Map<String, Object>> ，
List<Map<String, Object>> list3 = new ArrayList<Map<String,Object>>();
List<Map<String, Object>> list4 = new ArrayList<Map<String,Object>>();
Map<String, Object> map1 = new HashMap<String, Object>();
map1.put("name", "zhangsan");
map1.put("age", 18);
map1.put("address", "dalian");
Map<String, Object> map2 = new HashMap<String, Object>();
map2.put("name", " ");
map2.put("age", " ");
map2.put("address", " ");
list3.add(map1);
list3.add(map2);
Map<String, Object> map3 = new HashMap<String, Object>();
map3.put("name", " ");
map3.put("age", " ");
map3.put("address", " ");
list4.add(map2);
list4.add(map1);
list3.add(map3);
System.out.println(list3);
System.out.println(list4);
Collection intersection = CollectionUtils.intersection(list3, list4);
System.out.println(intersection);//[{address=dalian, name=zhangsan, age=18}]
//
boolean equalCollection = CollectionUtils.isEqualCollection(list3, list4);
System.out.println(equalCollection);
param2 param1，
System.out.println(list3);//[{address=dalian, name=zhangsan, age=18}, {address= , name= , age= }, {address= , name= , age= }]
System.out.println(list4);//[{address= , name= , age= }, {address=dalian, name=zhangsan, age=18}]
boolean properSubCollection = CollectionUtils.isProperSubCollection(list4, list3);
System.out.println(properSubCollection);//true
// ， （ ）
System.out.println(list);//[zhangsan, dalian, gateway, gateway, 28, 35]
Collection predicatedCollection = CollectionUtils.predicatedCollection(list, new Predicate() {
@Override
public boolean evaluate(Object object) {
if(StringUtils.isNumeric(object.toString())) {
return false;
}
return true;
}
});
System.out.println(predicatedCollection);//Exception in thread "main" java.lang.IllegalArgumentException: Cannot add Object '28' - Predicate rejected it
List<String> list2 = new ArrayList<String>();
list2.add("gateway");
System.out.println(list);
System.out.println(list2);
// list1 list2
Collection removeAll = CollectionUtils.removeAll(list, list2);
System.out.println(removeAll);
//
String[] array = new String[] {"zs","ls","ww"};
System.out.println(StringUtils.join(array, ","));//zs,ls,ww
CollectionUtils.reverseArray(array);
System.out.println(StringUtils.join(array, ","));//ww,ls,zs
list1 list2
List<String> list2 = new ArrayList<String>();
list2.add("zhangsan");
list2.add("dalian");
Collection subtract = CollectionUtils.subtract(list, list2);
System.out.println(subtract);
//
Collection collect = CollectionUtils.collect(list, new Transformer() {
@Override
public Object transform(Object arg0) {
if(StringUtils.isNumeric(arg0.toString())) {
return 15;
}
return arg0;
}
});
System.out.println(list);//[zhangsan, dalian, 28, 35]
System.out.println(collect);//[zhangsan, dalian, 15, 15]
// ，
System.out.println(list);//[zhangsan, dalian, gateway, gateway, 28, 35]
CollectionUtils.transform(list, new Transformer() {
@Override
public Object transform(Object input) {
if(StringUtils.isNumeric(input.toString())) {
return 15;
}
return input;
}
});
System.out.println(list);//[zhangsan, dalian, gateway, gateway, 15, 15]
List<String> list2 = new ArrayList<String>();
list2.add("docker");
list2.add("zhangsan");
System.out.println(list);
System.out.println(list2);
// list list2 ， list2
Collection union = CollectionUtils.union(list, list2);
System.out.println(union);
}
private static void work(Object obj){
System.out.println(" : ，"+obj);
}
private static void arrayUtilsTest() {
String[] array =new String[] {"zs", "ls"};
//
Object[] add = ArrayUtils.add(array, "ww");
System.out.println(StringUtils.join(add, ","));//zs,ls,ww
//
String[] array2 =new String[] {"ww", "ss"};
Object[] addAll = ArrayUtils.addAll(array1, array2);
System.out.println(StringUtils.join(addAll, ","));//zs,ls,ww,ss
//
Object[] clone = ArrayUtils.clone(array);
System.out.println(StringUtils.join(clone, ","));//zs,ls
boolean contains = ArrayUtils.contains(array, "ww");
boolean contains1 = ArrayUtils.contains(array, "zs");
System.out.println(contains+","+contains1);//false,true
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