JAva API学習例
23581 ワード
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.RandomAccessFile;
import java.lang.ref.SoftReference;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.net.FileNameMap;
import java.text.SimpleDateFormat;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.BitSet;
import java.util.Calendar;
import java.util.Collection;
import java.util.Collections;
import java.util.Date;
import java.util.EnumSet;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Hashtable;
import java.util.IdentityHashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.PriorityQueue;
import java.util.Queue;
import java.util.Random;
import java.util.Set;
import java.util.Stack;
import java.util.StringTokenizer;
import java.util.TimeZone;
import java.util.Timer;
import java.util.TimerTask;
import java.util.TreeMap;
import java.util.TreeSet;
import java.util.UUID;
import java.util.Vector;
import java.util.WeakHashMap;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;
import java.util.zip.ZipOutputStream;
/**
*
* 2012-11-28
* @author qq:542335496
*
*/
public class TestAPI {
enum Sex {
MAN, WOMEN
}
@SuppressWarnings("unused")
private class Person {
private Integer id;
private String name;
public Person() {
};
public Person(Integer id, String name) {
this.id = id;
this.name = name;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
@SuppressWarnings("unchecked")
public static void main(String[] args) throws Exception {
/** */
Collection collection;
{
collection=new ArrayList();
collection.addAll(Arrays.asList(1,2,3,4,5,6,7,8,9));
/** ， */
if(true){
return ;
}
}
/** */
List list;
/** */
ArrayList arrayList;
/** */
LinkedList linkedList;
/** hashmap */
LinkedHashMap linkedHashMap;
{
arrayList=new ArrayList();
for(int i=0;i<15;i++){
arrayList.add(i);
}
System.out.println(arrayList);
linkedList=new LinkedList();
linkedList.addAll(arrayList);
System.out.println(linkedList);
linkedHashMap=new LinkedHashMap();
for(int i=0;i<15;i++){
linkedHashMap.put(i, "value"+i);
}
System.out.println(linkedHashMap);
System.out.println(arrayList.contains(14));
System.out.println(linkedList.indexOf(11));
System.out.println(linkedList.offer(100));
System.out.println(linkedList.peekLast());
System.out.println(linkedList.peek());
System.out.println(linkedList.remove(2));
System.out.println(linkedList);
Set set=linkedHashMap.keySet();
Set> entrySet=linkedHashMap.entrySet();
Iterator iterator=set.iterator();
while(iterator.hasNext()){
Integer key=iterator.next();
String value=linkedHashMap.get(key);
System.out.print(" key="+key+" value="+value);
}
System.out.println();
if(true){
return ;
}
}
/** */
Queue queue;
/** */
ArrayDeque arrayDeque;
/** */
PriorityQueue priorityQueue;
ConcurrentLinkedQueue concurrentLinkedQueue;
{
priorityQueue = new PriorityQueue();
priorityQueue.addAll(Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10));
System.out.println(priorityQueue);
arrayDeque=new ArrayDeque();
arrayDeque.addAll(priorityQueue);
System.out.println(arrayDeque.pop());
System.out.println(arrayDeque.poll());
//
arrayDeque.push(500);
arrayDeque.push(200);
//
System.out.println(arrayDeque.remove());
//
System.out.println(arrayDeque.add(99));
System.err.println(arrayDeque);
// , ？
//priorityQueue.poll();
show(priorityQueue);
Iterator iterator=priorityQueue.iterator();
while(iterator.hasNext()){
Integer data=iterator.next();
System.out.print("\t"+data);
}
System.out.println();
concurrentLinkedQueue=new ConcurrentLinkedQueue();
concurrentLinkedQueue.addAll(priorityQueue);
System.out.println(concurrentLinkedQueue);
if(true){
return ;
}
}
/** */
Stack stack;
{
stack = new Stack();
for (int i = 0; i < 10; i++) {
stack.add(i);
}
show(stack);
stack.addElement(111);
// ，
System.out.println(stack.capacity());
System.out.println(stack.size());
System.out.println(stack.indexOf(111));
System.out.println(stack.remove(1));
System.out
.println(stack.retainAll(Arrays.asList(3, 4, 5, 6, 7, 8)));
System.out.println(stack.search(3));
System.out.println(stack.toString());
System.out.println(stack.peek());
stack.pop();
stack.pop();
stack.push(100);
System.out.println(stack.subList(1, 4));
show(stack);
stack.removeAllElements();
System.out.println(stack.isEmpty());
}
/** */
Vector vector;
{
vector = new Vector();
for (int i = 0; i < 20; i++) {
vector.add(i);
}
show(vector);
vector.addElement(1999);
// ，
System.out.println(vector.capacity());
System.out.println(vector.contains(1));
System.out.println(vector.containsAll(Arrays.asList(1, 2, 3, 4, 5,
6)));
System.out.println(vector.lastIndexOf(19));
System.out.println(vector.remove(1));
System.out.println(vector.removeAll(Arrays.asList(1, 2, 3, 4, 5, 6,
7, 8, 9)));
System.out.println(vector.retainAll(Arrays.asList(10, 11, 12, 13,
14, 15, 60)));
System.out.println(vector.size());
System.out.println(vector.elementAt(2));
System.out.println(vector.firstElement());
System.out.println(vector.lastElement());
System.out.println(vector.subList(1, 5));
vector.ensureCapacity(52);
System.out.println(vector.size());
vector.removeAllElements();
System.out.println(vector.isEmpty());
show(vector);
}
System.out.println("========map=======");
Map map;
Hashtable hashtable;
HashMap hashMap;
// EnumMap enumMap;
/** map */
TreeMap treeMap;
// ConcurrentHashMap concurrentHashMap;
// ConcurrentMap concurrentMap;
WeakHashMap weakHashMap;
IdentityHashMap identityHashMap;
{
hashMap = new HashMap();
hashtable = new Hashtable();
treeMap = new TreeMap();
weakHashMap = new WeakHashMap();
identityHashMap = new IdentityHashMap();
for (int i = 0; i < 20; i++) {
hashMap.put(i, " " + i);
}
show(hashMap);
hashtable.putAll(hashMap);
treeMap.putAll(hashMap);
weakHashMap.putAll(hashMap);
identityHashMap.putAll(hashMap);
show(hashtable);
show(treeMap);
show(weakHashMap);
show(identityHashMap);
System.out.println(hashMap.containsKey(14));
System.out.println(hashMap.containsValue(" 5"));
System.out.println(hashMap.values());
System.out.println(hashtable.remove(1));
System.out.println(hashtable.values());
hashtable.clear();
System.out.println(hashtable.isEmpty());
}
System.out.println("========set=======");
// Set
Set set;
BitSet bitSet;
EnumSet enumSet;
HashSet hashSet;
/** set */
TreeSet treeSet;
/** hashset */
LinkedHashSet linkedHashSet;
Iterator iterator;
{
enumSet = EnumSet.noneOf(Sex.class);
hashSet = new HashSet();
treeSet = new TreeSet();
linkedHashSet = new LinkedHashSet();
// ？？
for (int i = 15; i > 0; i--) {
hashSet.add(i);
}
treeSet.addAll(hashSet);
linkedHashSet.addAll(hashSet);
enumSet.add(Sex.MAN);
enumSet.add(Sex.WOMEN);
show(hashSet);
show(treeSet);
show(linkedHashSet);
show(enumSet);
System.out.println(enumSet.size());
enumSet.clear();
System.out.println(enumSet.size());
System.out.println(enumSet.isEmpty());
System.out.println(hashSet.contains(10));
System.out.println(linkedHashSet.containsAll(hashSet));
linkedHashSet.remove(14);
System.out.println(linkedHashSet.containsAll(hashSet));
hashSet.removeAll(linkedHashSet);
show(hashSet);
Object[] objs = treeSet.toArray();
show(objs);
Integer[] strs = treeSet.toArray(new Integer[0]);
show(strs);
for (Iterator iterator2 = treeSet.iterator(); iterator2
.hasNext();) {
Integer data = iterator2.next();
System.out.print(data + "\t");
}
System.out.println();
}
//
java.util.StringTokenizer stringTokenizer;
{
String[] temps = "1,2,3,4,5,6".split(",");
show(temps);
stringTokenizer = new StringTokenizer("1,2,3,4,5,6,7,8,9", ",");
String[] datas = new String[stringTokenizer.countTokens()];
int i = 0;
while (stringTokenizer.hasMoreTokens()) {
String str = stringTokenizer.nextToken();
System.out.print(str + "\t");
datas[i] = str;
i++;
}
System.out.println();
show(datas);
}
java.util.Calendar calendar;
java.util.Date date;
{
calendar = Calendar.getInstance();
int year = calendar.get(Calendar.YEAR);
int month = calendar.get(Calendar.MONTH) + 1;
int day = calendar.get(Calendar.DAY_OF_MONTH);
int hours = calendar.get(Calendar.HOUR_OF_DAY);
int minute = calendar.get(Calendar.MINUTE);
int second = calendar.get(Calendar.SECOND);
System.out.println(year + "-" + month + "-" + day + " " + hours
+ ":" + minute + ":" + second);
date = new Date();
System.out.println(date.after(new Date(
System.currentTimeMillis() + 1000)));
System.out.println(date.compareTo(new Date(System
.currentTimeMillis() - 1000)));
SimpleDateFormat dateFormat = new SimpleDateFormat(
"yyyy-MM-dd HH:mm:ss");
String str = dateFormat.format(date);
System.out.println(str);
}
java.util.Random random;
{
random = new Random();
System.out.println(random.nextBoolean());
System.out.println(random.nextDouble());
System.out.println(random.nextFloat());
System.out.println(random.nextInt());
System.out.println(random.nextInt(15));
System.out.println(random.nextLong());
byte[] datas = new byte[10];
random.nextBytes(datas);
System.out.println(datas);
random.setSeed(10000);
System.out.println(random.nextInt());
System.out.println(random.nextInt());
}
java.util.Scanner scanner;
java.util.Timer timer;
java.util.TimerTask timerTask;
{
timer = new Timer();
timerTask = new TimerTask() {
@SuppressWarnings("deprecation")
@Override
public void run() {
System.out.println(new Date().toLocaleString());
}
};
timer.schedule(timerTask, 1000, 1000);
// timerTask.run();
}
java.util.TimeZone timeZone;
{
System.gc();
System.out.println(UUID.randomUUID());
timeZone = TimeZone.getDefault();
System.out.println(timeZone.getDisplayName());
/**
* String[] strs=timeZone.getAvailableIDs(); for(String str:strs){
* System.out.println(str); }
*/
}
java.lang.Character character;
{
character = Character.valueOf('f');
int data = Character.digit(character, 16);
System.out.println(data);
int data2 = Character.digit(5, 16);
System.out.println(data2);
System.out.println(Character.isDigit('b'));
System.out.println(Character.reverseBytes('a'));
}
java.lang.Process process;
{
process = Runtime.getRuntime().exec("cmd /c dir", null,
new File("."));
BufferedReader bufferedReader = new BufferedReader(
new InputStreamReader(process.getInputStream(), "GBK"));
String line;
while ((line = bufferedReader.readLine()) != null) {
System.out.println(line);
}
// ///
System.out.println("=======");
ProcessBuilder builder = new ProcessBuilder("java");
builder.directory(new File(
"C:\\Program Files\\Java\\jdk1.6.0_30\\bin"));
Process process2 = builder.start();
BufferedReader bufferedReader2 = new BufferedReader(
new InputStreamReader(process2.getInputStream(), "GBK"));
while ((line = bufferedReader2.readLine()) != null) {
System.out.println(line);
}
}
java.lang.Class class1;
java.lang.CharSequence charSequence;
{
java.lang.ClassLoader.getSystemResource("file.xml");
charSequence = "wujianhua";
System.out.println(charSequence.charAt(6));
System.out.println(charSequence.length());
System.out.println(charSequence.subSequence(2, 5));
System.out.println(charSequence.hashCode());
}
java.lang.Number number;
java.lang.Package package1;
{
/**
* Package[] datas=Package.getPackages(); for(Package
* package2:datas){ System.out.println(package2.getName()); }
*/
package1 = Package.getPackage("java.lang");
System.out.println(package1.getImplementationTitle());
System.out.println(package1.getImplementationVendor());
System.out.println(package1.getImplementationVersion());
System.out.println(package1.getSpecificationTitle());
System.out.println(package1.getSpecificationVendor());
System.out.println(package1.getSpecificationVersion());
System.out.println(package1.getDeclaredAnnotations());
System.out.println(package1.isSealed());
}
java.lang.String string;
{
System.out.println("".isEmpty());
}
//
java.util.Comparator comparator;
java.util.RandomAccess randomAccess;
java.util.SortedMap sortedMap;
java.util.SortedSet sortedSet;
java.applet.Applet applet;
java.io.File file;
java.io.FileFilter fileFilter;
java.io.PrintWriter printWriter;
{
try {
printWriter = new PrintWriter(new BufferedWriter(
new FileWriter("writer.txt")));
printWriter.append(" ");
printWriter.append(",");
printWriter.append(" ");
printWriter.println();
printWriter.print(" ");
printWriter.write(" ");
printWriter.println(new BigInteger("123456789"));
printWriter.flush();
printWriter = new PrintWriter(System.out);
printWriter.println(" ");
printWriter.write(" ");
printWriter.flush();
printWriter.close();
} catch (IOException e) {
e.printStackTrace();
}
}
java.io.RandomAccessFile randomAccessFile;
{
try {
randomAccessFile = new RandomAccessFile("test.txt", "rw");
randomAccessFile.write(" ".getBytes());
randomAccessFile.writeUTF(" ");
randomAccessFile.write(22);
// again
randomAccessFile.write(" ".getBytes());
randomAccessFile.writeUTF(" ");
randomAccessFile.write(21);
randomAccessFile.close();
RandomAccessFile randomAccessFile2 = new RandomAccessFile(
"test.txt", "rw");
randomAccessFile2.skipBytes(6);
System.out.println(randomAccessFile2.getFilePointer());
System.out.println(randomAccessFile2.readUTF());
randomAccessFile2.skipBytes(1);
byte[] names = new byte[6];
randomAccessFile2.read(names);
System.out.println(new String(names));
randomAccessFile2.seek(0);
randomAccessFile2.read(names);
System.out.println(new String(names));
} catch (Exception e) {
e.printStackTrace();
}
if (true) {
return;
}
}
/** */
java.lang.ref.SoftReference softReference;
{
Integer data = 0;
softReference = new SoftReference(data);
data = softReference.get();
if (data == null) {
data = softReference.get();
}
System.out.println(data);
}
java.math.BigDecimal bigDecimal = new BigDecimal("123456789");
System.out.println("====bigInteger===");
java.math.BigInteger bigInteger = new BigInteger("123456789");
{
System.out.println(bigInteger.abs() + "\t" + bigInteger.bitCount()
+ "\t" + bigInteger.bitLength());
System.out.println(bigInteger.doubleValue());
System.out.println(bigInteger.floatValue());
System.out.println(bigInteger.longValue());
System.out.println(bigInteger.intValue());
System.out.println(bigInteger.divide(new BigInteger("11111111")));
// System.out.println(bigInteger);
System.out.println(bigInteger.multiply(new BigInteger("2")));
System.out
.println(bigInteger.subtract(new BigInteger("111111111")));
System.out.println(bigInteger.add(new BigInteger("111111111")));
}
java.net.HttpURLConnection httpURLConnection;
java.net.Socket socket;
java.net.URI uri;
java.net.URLConnection urlConnection;
java.net.FileNameMap fileNameMap = new FileNameMap() {
@Override
public String getContentTypeFor(String fileName) {
return "txt";
}
};
System.out.println(fileNameMap.getContentTypeFor("d:\test.txt"));
java.util.regex.Matcher matcher;
java.util.regex.Pattern pattern;
System.out.println("====zipFile===");
java.util.zip.ZipFile zipFile;
{
File file2 = new File(".");
System.out.println(file2.getAbsolutePath());
try {
zipFile("file.doc", "file.zip", "file.doc");
unZip("file.zip", "d:/test/");
} catch (Exception e) {
e.printStackTrace();
}
}
javax.crypto.Cipher cipher;
System.out.println("====collections===");
Collections collections;
{
List list2 = new ArrayList();
Collections.addAll(list2, 12, 45, 62, 98, 32, 41, 15, 24, 3, 4);
Collections.sort(list2);//
show(list2);
int pos = 0;
if ((pos = Collections.binarySearch(list2, 15)) != -1) {
System.out.println(" ：" + pos);
}
;
// ， list3.size()>0,
List list3 = new ArrayList(Arrays
.asList(new Integer[list2.size()]));
System.out.println(list3.size());
Collections.copy(list3, list2);//
show(list3);
System.out.println(" ：" + Collections.max(list3));
System.out.println(" :" + Collections.min(list3));
//
Enumeration enumerations = Collections.enumeration(list2);
show(enumerations);
List list4 = new ArrayList();
//
list4 = Collections.synchronizedList(list3);
show(list4);
//
Collections.reverse(list3);
show(list3);
}
}
@SuppressWarnings("unchecked")
private static void show(Queue queue) {
for (Object obj : queue) {
System.out.print("\t" + obj);
}
System.out.println();
}
private static void show(Map maps) {
Set keySet = maps.keySet();
// Set> entrySet=maps.entrySet();
for (Iterator iterator = keySet.iterator(); iterator.hasNext();) {
Integer key = iterator.next();
String value = maps.get(key);
System.out.print("key=" + key + "\tvalue=" + value + "\t");
}
System.out.println();
}
private static void show(Object[] objs) {
for (Object data : objs) {
System.out.print(data + "\t");
}
System.out.println();
}
@SuppressWarnings("unchecked")
private static void show(Set hashSet) {
for (Object data : hashSet) {
System.out.print(data + "\t");
}
System.out.println();
}
public static void show(List datas) {
for (Integer data : datas) {
System.out.print(data + "\t");
}
System.out.println();
}
public static void show(Vector datas) {
for (Integer data : datas) {
System.out.print(data + "\t");
}
System.out.println();
}
public static void show(Enumeration datas) {
for (Enumeration e = datas; e.hasMoreElements();) {
System.out.print(e.nextElement() + "\t");
}
System.out.println();
}
public static void show(String[] datas) {
for (String data : datas) {
System.out.print(data + "\t");
}
System.out.println();
}
/** */
public static void zipFile(String srcFilePath, String destZipFilePath,
String fileName) throws Exception {
File file = new File(destZipFilePath);
int leng = 0;
byte[] b = new byte[1024];
//
ZipOutputStream zos = new ZipOutputStream(new FileOutputStream(file));
//
FileInputStream fis = new FileInputStream(srcFilePath);
//
ZipEntry z1 = new ZipEntry(fileName);
zos.putNextEntry(z1);
while ((leng = fis.read(b)) != -1) {
zos.write(b, 0, leng);
}
zos.close();
fis.close();
}
@SuppressWarnings("unchecked")
public static void unZip(String fileName, String unZipDir) throws Exception {
// ， ，
File f = new File(unZipDir);
if (!f.exists()) {
f.mkdirs();
}
BufferedOutputStream dest = null;
BufferedInputStream is = null;
ZipEntry entry;
ZipFile zipfile = new ZipFile(fileName);
Enumeration e = zipfile.entries();
while (e.hasMoreElements()) {
entry = (ZipEntry) e.nextElement();
// System.out.println("Extracting: " + entry);
is = new BufferedInputStream(zipfile.getInputStream(entry));
int count;
byte data[] = new byte[1024];
FileOutputStream fos = new FileOutputStream(unZipDir + "/"
+ entry.getName());
// System.out.println("entry.getName(): " + entry.getName());
dest = new BufferedOutputStream(fos, 1024);
while ((count = is.read(data, 0, 1024)) != -1) {
dest.write(data, 0, count);
}
dest.flush();
dest.close();
is.close();
}
}
public static boolean makeDir(String unZipDir) {
boolean b = false;
try {
File f = new File(unZipDir);
if (!f.exists()) {
b = f.mkdirs();
}
} catch (Exception e) {
e.printStackTrace();
return b;
}
return b;
}
}