一、FileUtils
-
private static void fileUtilsTest() {
-
try {
-
//读取文件内容
-
String readFileToString = FileUtils.readFileToString(
new File(
"D:\\guor\\data\\test20211022000000.txt"));
-
System.out.println(readFileToString);
-
//删除文件夹
-
FileUtils.deleteDirectory(
new File(
"D:\\guor1\\data1"));
-
FileUtils.deleteQuietly(
new File(
"D:\\guor\\data"));
-
//清空文件夹
-
FileUtils.cleanDirectory(
new File(
"D:\\guor\\data"));
-
//判断文件内容是否一致
-
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\\中文20211021100000.txt"),
new File(
"D:\\guor\\data\\中文New20211022100000.txt"));
-
System.out.println(contentEquals+
","+contentEquals2);
-
//拷贝特定类型的文件
-
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);
-
//获取某文件夹下特定格式文件
-
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));
-
//获取系统temp文件夹路径
-
File tempDirectory = FileUtils.getTempDirectory();
-
System.out.println(tempDirectory);
-
//获取系统用户文件夹路径
-
File userDirectory = FileUtils.getUserDirectory();
-
System.out.println(userDirectory);
-
-
//查看是否是新建的文件夹
-
SimpleDateFormat sdf =
new SimpleDateFormat(
"yyyyMMddHHmmss" );
-
Date parse = sdf.parse(
"20210206134900");
-
boolean fileNewer = FileUtils.isFileNewer(
new File(
"D:\\guor\\data"), parse);
-
System.out.println(fileNewer);
-
//更新文件修改时间，如果不存在，则新建；
-
FileUtils.touch(
new File(
"D:\\guor\\data\\test20211022000000.txt"));
-
//延迟查看文件是否存在
-
boolean waitFor = FileUtils.waitFor(
new File(
"D:\\guor\\data\\testNew20211021000000.txt"),
5);
-
System.out.println(waitFor);
-
}
catch (Exception e) {
-
System.out.println(e);
-
}
-
}
-
//根据文件修改时间排序
-
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());
-
}
-
}
二、StringUtil
-
private static void stringUtilsTest() {
-
String str =
"hello world";
-
//将第一个字符大写
-
String capitalize = StringUtils.capitalize(str);
-
System.out.println(capitalize);
//Hello
-
//两边空格补齐
-
String center = StringUtils.center(str,
7);
-
System.out.println(center);
// hello
-
String center = StringUtils.center(str,
7,
"*");
-
System.out.println(center);
//*hello*
-
//chomp剔除字符串最后一个是\n或\r\或\r\n
-
String chomp = StringUtils.chomp(str);
-
System.out.println(chomp);
-
//chop剔除字符串最后一个字符（如果最后一个是\n或\r\或\r\n也剔除掉）
-
String chop = StringUtils.chop(str);
-
System.out.println(chop);
//hello worl
-
//是否包含任意字符
-
boolean containsAny = StringUtils.containsAny(str,
"W");
-
System.out.println(containsAny);
-
//是否包含任意字符，忽略大小写
-
containsAny = StringUtils.containsIgnoreCase(str,
"W");
-
System.out.println(containsAny);
-
-
//有意思
-
int indexOfAnyBut = StringUtils.indexOfAnyBut(str,
"hello orld");
-
System.out.println(indexOfAnyBut);
-
-
//两个字符串从第几位开始不同
-
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);
-
-
//判断是否是正整数
-
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
-
//判断是否是正整数或空格
-
boolean isNumeric = StringUtils.isNumericSpace(str);
-
-
//将数组变为字符串，并添加字符进行分割
-
Object[] array =
new Object[] {
"zs",
18,
"男",
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,
"男",
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
-
-
//分别替换
-
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.
-
-
//只替换第一个匹配的字符串
-
String replaceOnce = StringUtils.replaceOnce(
"hello world,hello boy,hello girl.",
"hello",
"say");
-
System.out.println(replaceOnce);
//say world,hello boy,hello girl.
-
-
//截取某字符后面的部分
-
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
-
}
三、CollectionUtils
-
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");
-
//查找第一个符合条件的元素
-
Object find = CollectionUtils.find(list,
new Predicate() {
-
@Override
-
public boolean evaluate(Object arg0) {
-
if(StringUtils.isNumeric(arg0.toString())) {
-
return
false;
-
}
-
return
true;
-
}
-
});
-
-
//排除不符合条件的元素
-
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");
-
//查看两个集合中是否有相同的元素
-
boolean containsAny = CollectionUtils.containsAny(list, list2);
-
System.out.println(containsAny);
//true
-
-
//查找集合中某元素的个数
-
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);
-
-
//查找集合中是否存在某元素
-
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);
-
-
//删除集合中的某些元素
-
System.out.println(list);
//[zhangsan, dalian, 打法, 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, 打法]
-
-
//查找集合中符合条件的第一个元素
-
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
-
-
//闭包回调函数
-
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);
-
-
//查找集合中元素的个数
-
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}
-
-
//查找两个集合中的相同元素
-
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);
-
-
//获取两个List<Map<String, Object>>中相同的部分，可以用于对比两个库中的相同表数据是否相等
-
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",
"张三");
-
map2.put(
"age",
"十八");
-
map2.put(
"address",
"大连");
-
list3.add(map1);
-
list3.add(map2);
-
-
Map<String, Object> map3 =
new HashMap<String, Object>();
-
map3.put(
"name",
"李四");
-
map3.put(
"age",
"十八");
-
map3.put(
"address",
"大连");
-
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}]
-
-
//判断两个集合是否相同
-
boolean equalCollection = CollectionUtils.isEqualCollection(list3, list4);
-
System.out.println(equalCollection);
-
-
判断param2是否包含param1，且不能完全相同
-
System.out.println(list3);
//[{address=dalian, name=zhangsan, age=18}, {address=大连, name=张三, age=十八}, {address=大连, name=李四, age=十八}]
-
System.out.println(list4);
//[{address=大连, name=张三, age=十八}, {address=dalian, name=zhangsan, age=18}]
-
boolean properSubCollection = CollectionUtils.isProperSubCollection(list4, list3);
-
System.out.println(properSubCollection);
//true
-
-
//断定某集合是否含有某元素，如果包含则抛异常（我觉得应该少用为妙）
-
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);
-
//删除list1中的list2
-
Collection removeAll = CollectionUtils.removeAll(list, list2);
-
System.out.println(removeAll);
-
-
//反转数组
-
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
-
-
删除list1中的list2
-
List<String> list2 =
new ArrayList<String>();
-
list2.add(
"zhangsan");
-
list2.add(
"dalian");
-
Collection subtract = CollectionUtils.subtract(list, list2);
-
System.out.println(subtract);
-
-
//更改集合中的特定值
-
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]
-
-
//更改集合中的特定值，改变集合本身
-
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);
-
//将list和list2中的元素合并，但去除list2中的重复元素
-
Collection union = CollectionUtils.union(list, list2);
-
System.out.println(union);
-
}
-
private static void work(Object obj){
-
System.out.println(
"闭包回调函数:我是数字，"+obj);
-
}
四、ArrayUtils
-
private static void arrayUtilsTest() {
-
String[] array =
new String[] {
"zs",
"ls"};
-
-
//增加元素
-
Object[] add = ArrayUtils.add(array,
"ww");
-
System.out.println(StringUtils.join(add,
","));
//zs,ls,ww
-
-
//合并数组
-
String[] array2 =
new String[] {
"ww",
"ss"};
-
Object[] addAll = ArrayUtils.addAll(array1, array2);
-
System.out.println(StringUtils.join(addAll,
","));
//zs,ls,ww,ss
-
-
//克隆数组
-
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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转载：https://blog.csdn.net/guorui_java/article/details/115529750
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