public static void main(String[] args) {
ArrayList nums = new ArrayList();
nums.add(2);
nums.add(-5);
nums.add(3);
nums.add(0);
// 输出:[2, -5, 3, 0]
System.out.println(nums);
// 输出最大元素，将输出3
System.out.println(Collections.max(nums));
// 输出最小元素，将输出-5
System.out.println(Collections.min(nums));
// 将nums中的0使用1来代替
Collections.replaceAll(nums, 0, 1);
// 输出:[2, -5, 3, 1]
System.out.println(nums);
// 判断-5 在List集合中出现的次数，返回1
System.out.println(Collections.frequency(nums, -5));
// 对nums集合排序
Collections.sort(nums);
// 输出:[-5, 1, 2, 3]
System.out.println(nums);
// 只有排序后的List集合才可用二分法查询，输出3
System.out.println(Collections.binarySearch(nums, 3));
}
@Override
public Movie update(Movie movie) {
// TODO Auto-generated method stub
for (Movie mov : movielist) {
if (mov.getId().equals(movie.getId())) {
Collections.replaceAll(movielist, mov, movie);
} else throw new IllegalArgumentException("This movie is not present in the list");
}
if (movielist.contains(movie)) return movie;
else return null;
}
public static int countUniqueValues(Map<String, Integer> map) {
int cnt = 0;
ArrayList<Integer> valueList = new ArrayList<Integer>(map.values());
for (Integer val : valueList) {
if (val != -Integer.MAX_VALUE) {
Collections.replaceAll(valueList, val, -Integer.MAX_VALUE);
cnt++;
}
}
return cnt;
}
public void addSubBuild(SubBuild subBuild) {
String key =
subBuild
.getPhaseName()
.concat(subBuild.getJobName())
.concat(String.valueOf(subBuild.getBuildNumber()));
if (subBuildsMap.containsKey(key)) {
SubBuild e = subBuildsMap.get(key);
Collections.replaceAll(getSubBuilds(), e, subBuild);
} else {
getSubBuilds().add(subBuild);
}
subBuildsMap.put(key, subBuild);
}
public static void replaceTheValueOfExistingElementInArrayList() {
ArrayList<String> strings = new ArrayList<String>(200);
strings.add("a");
strings.add("b");
strings.add("c");
strings.add("d");
strings.add("b");
strings.set(2, "z");
Collections.replaceAll(strings, "b", "z");
}
public static void main(String[] args) {
print(list);
print(
"'list' disjoint (Four)?: "
+ Collections.disjoint(list, Collections.singletonList("Four")));
print("max: " + Collections.max(list));
print("min: " + Collections.min(list));
print("max w/ comparator: " + Collections.max(list, String.CASE_INSENSITIVE_ORDER));
print("min w/ comparator: " + Collections.min(list, String.CASE_INSENSITIVE_ORDER));
List<String> sublist = Arrays.asList("Four five six".split(" "));
print("indexOfSubList: " + Collections.indexOfSubList(list, sublist));
print("lastIndexOfSubList: " + Collections.lastIndexOfSubList(list, sublist));
Collections.replaceAll(list, "one", "Yo");
print("replaceAll: " + list);
Collections.reverse(list);
print("reverse: " + list);
Collections.rotate(list, 3);
print("rotate: " + list);
List<String> source = Arrays.asList("in the matrix".split(" "));
Collections.copy(list, source);
print("copy: " + list);
Collections.swap(list, 0, list.size() - 1);
print("swap: " + list);
Collections.shuffle(list, new Random(47));
print("shuffled: " + list);
Collections.fill(list, "pop");
print("fill: " + list);
print("frequency of 'pop': " + Collections.frequency(list, "pop"));
List<String> dups = Collections.nCopies(3, "snap");
print("dups: " + dups);
print("'list' disjoint 'dups'?: " + Collections.disjoint(list, dups));
// Getting an old-style Enumeration:
Enumeration<String> e = Collections.enumeration(dups);
Vector<String> v = new Vector<String>();
while (e.hasMoreElements()) v.addElement(e.nextElement());
// Converting an old-style Vector
// to a List via an Enumeration:
ArrayList<String> arrayList = Collections.list(v.elements());
print("arrayList: " + arrayList);
}
public static Geometry replace(Geometry parent, Geometry original, Geometry replacement) {
List elem = extractElements(parent, false);
Collections.replaceAll(elem, original, replacement);
return parent.getFactory().buildGeometry(elem);
}
public static void main(String args[]) throws FileNotFoundException, IOException {
System.out.println("Gathering data...");
// Use char[] for ease in building strings, despite only using 8 bits.
int numElements = 65536;
char[] info = new char[numElements];
for (int i = 0; i < info.length; i++) {
if (i == '\n' || i == '\r') info[i] = NEWLINE_CODE;
else if (i == ' ' || i == '\t' || i == '\f') info[i] = SPACE_CODE;
else if (i < 128 && Character.isLowerCase((char) i)) info[i] = LOWER_CODE; // Ascii lower case
else if (i < 128 && Character.isUpperCase((char) i)) info[i] = UPPER_CODE; // Ascii upper case
else if (i < 128 && Character.isDigit((char) i)) info[i] = DIGIT_CODE; // Ascii digit
else if (Character.isJavaIdentifierStart((char) i)) info[i] = OTHER_LETTER_CODE;
else if (Character.isJavaIdentifierPart((char) i)) info[i] = OTHER_DIGIT_CODE;
else {
info[i] = BAD_CODE;
numElements--;
}
}
System.out.println("Compressing tables...");
int bestShift = 0;
int bestEst = info.length;
String bestBlkStr = null;
for (int i = 3; i < 11; i++) {
int blkSize = 1 << i;
Map blocks = new HashMap();
List blkArray = new ArrayList();
System.out.print("shift: " + i);
for (int j = 0; j < info.length; j += blkSize) {
String key = new String(info, j, blkSize);
if (blocks.get(key) == null) {
blkArray.add(key);
blocks.put(key, new Integer(blkArray.size()));
}
}
int blkNum = blkArray.size();
int blockLen = blkNum * blkSize;
System.out.print(" before " + blockLen);
//
// Try to pack blkArray, by finding successively smaller matches
// between heads and tails of blocks.
//
for (int j = blkSize - 1; j > 0; j--) {
Map tails = new HashMap();
for (int k = 0; k < blkArray.size(); k++) {
String str = (String) blkArray.get(k);
if (str == null) continue;
String tail = str.substring(str.length() - j);
List l = (List) tails.get(tail);
if (l == null) tails.put(tail, new LinkedList(Collections.singleton(new Integer(k))));
else l.add(new Integer(k));
}
//
// Now calculate the heads, and merge overlapping blocks
//
block:
for (int k = 0; k < blkArray.size(); k++) {
String tomerge = (String) blkArray.get(k);
if (tomerge == null) continue;
while (true) {
String head = tomerge.substring(0, j);
LinkedList entry = (LinkedList) tails.get(head);
if (entry == null) continue block;
Integer other = (Integer) entry.removeFirst();
if (other.intValue() == k) {
if (entry.size() > 0) {
entry.add(other);
other = (Integer) entry.removeFirst();
} else {
entry.add(other);
continue block;
}
}
if (entry.size() == 0) tails.remove(head);
//
// A match was found.
//
String merge = blkArray.get(other.intValue()) + tomerge.substring(j);
blockLen -= j;
blkNum--;
if (other.intValue() < k) {
blkArray.set(k, null);
blkArray.set(other.intValue(), merge);
String tail = merge.substring(merge.length() - j);
List l = (List) tails.get(tail);
Collections.replaceAll(l, new Integer(k), other);
continue block;
}
blkArray.set(k, merge);
blkArray.set(other.intValue(), null);
tomerge = merge;
}
}
}
StringBuffer blockStr = new StringBuffer(blockLen);
for (int k = 0; k < blkArray.size(); k++) {
String str = (String) blkArray.get(k);
if (str != null) blockStr.append(str);
}
if (blockStr.length() != blockLen) throw new Error("Unexpected blockLen " + blockLen);
int estimate = blockLen + (info.length >> (i - 1));
System.out.println(" after merge " + blockLen + ": " + estimate + " bytes");
if (estimate < bestEst) {
bestEst = estimate;
bestShift = i;
bestBlkStr = blockStr.toString();
}
}
int blkSize = 1 << bestShift;
char[] blocks = new char[info.length / blkSize];
for (int j = 0; j < info.length; j += blkSize) {
String key = new String(info, j, blkSize);
int index = bestBlkStr.indexOf(key);
if (index == -1) throw new Error("Unexpected index for " + j);
blocks[j >> bestShift] = (char) (index - j);
}
//
// Process the code.h file
//
System.out.println("Generating code.h with shift of " + bestShift);
PrintStream hfile = new PrintStream(new FileOutputStream("code.h"));
printHeader(hfile, new String[] {"\"platform.h\""});
hfile.println("#ifndef code_INCLUDED");
hfile.println("#define code_INCLUDED");
hfile.println();
hfile.println("class Code");
hfile.println("{");
hfile.println(" //");
hfile.println(" // To facilitate the scanning, the character set is partitioned into");
hfile.println(" // 8 categories using the array CODE. These are described below");
hfile.println(" // together with some self-explanatory functions defined on CODE.");
hfile.println(" //");
hfile.println(" enum {");
hfile.println(" SHIFT = " + bestShift + ",");
hfile.println(" NEWLINE_CODE = " + NEWLINE_CODE + ',');
hfile.println(" SPACE_CODE = " + SPACE_CODE + ',');
hfile.println(" BAD_CODE = " + BAD_CODE + ',');
hfile.println(" DIGIT_CODE = " + DIGIT_CODE + ',');
hfile.println(" OTHER_DIGIT_CODE = " + OTHER_DIGIT_CODE + ',');
hfile.println(" LOWER_CODE = " + LOWER_CODE + ',');
hfile.println(" UPPER_CODE = " + UPPER_CODE + ',');
hfile.println(" OTHER_LETTER_CODE = " + OTHER_LETTER_CODE);
hfile.println(" };");
hfile.println();
hfile.println(" static char codes[" + bestBlkStr.length() + "];");
hfile.println(" static u2 blocks[" + blocks.length + "];");
hfile.println();
hfile.println();
hfile.println("public:");
hfile.println();
hfile.println(" static inline void SetBadCode(wchar_t c)");
hfile.println(" {");
hfile.println(" codes[(u2) (blocks[c >> SHIFT] + c)] = BAD_CODE;");
hfile.println(" }");
hfile.println();
hfile.println(" static inline void CodeCheck(wchar_t c)");
hfile.println(" {");
hfile.println(" assert((u2) (blocks[c >> SHIFT] + c) < " + bestBlkStr.length() + ");");
hfile.println(" }");
hfile.println();
hfile.println(" static inline bool CodeCheck(void)");
hfile.println(" {");
hfile.println(" for (int i = 0; i <= 0xffff; i++)");
hfile.println(" CodeCheck((wchar_t) i);");
hfile.println(" return true;");
hfile.println(" }");
hfile.println();
hfile.println(" //");
hfile.println(" // \\r characters are replaced by \\x0a in Stream::ProcessInput().");
hfile.println(" //");
hfile.println(" static inline bool IsNewline(wchar_t c)");
hfile.println(" {");
hfile.println(" return c == '\\x0a';");
hfile.println(" }");
hfile.println();
hfile.println(" static inline bool IsSpaceButNotNewline(wchar_t c)");
hfile.println(" {");
hfile.println(" return codes[(u2) (blocks[c >> SHIFT] + c)] == SPACE_CODE;");
hfile.println(" }");
hfile.println();
hfile.println(" static inline bool IsSpace(wchar_t c)");
hfile.println(" {");
hfile.println(" return codes[(u2) (blocks[c >> SHIFT] + c)] <= SPACE_CODE;");
hfile.println(" }");
hfile.println();
hfile.println(" static inline bool IsDigit(wchar_t c)");
hfile.println(" {");
hfile.println(" return codes[(u2) (blocks[c >> SHIFT] + c)] == DIGIT_CODE;");
hfile.println(" }");
hfile.println();
hfile.println(" static inline bool IsOctalDigit(wchar_t c)");
hfile.println(" {");
hfile.println(" return c >= U_0 && c <= U_7;");
hfile.println(" }");
hfile.println();
hfile.println(" static inline bool IsHexDigit(wchar_t c)");
hfile.println(" {");
hfile.println(" return c <= U_f && (c >= U_a ||");
hfile.println(" (c >= U_A && c <= U_F) ||");
hfile.println(" (c >= U_0 && c <= U_9));");
hfile.println(" }");
hfile.println();
hfile.println(" static inline bool IsUpper(wchar_t c)");
hfile.println(" {");
hfile.println(" return codes[(u2) (blocks[c >> SHIFT] + c)] == UPPER_CODE;");
hfile.println(" }");
hfile.println();
hfile.println(" static inline bool IsLower(wchar_t c)");
hfile.println(" {");
hfile.println(" return codes[(u2) (blocks[c >> SHIFT] + c)] == LOWER_CODE;");
hfile.println(" }");
hfile.println();
hfile.println(" static inline bool IsAlpha(wchar_t c)");
hfile.println(" {");
hfile.println(" return codes[(u2) (blocks[c >> SHIFT] + c)] >= LOWER_CODE;");
hfile.println(" }");
hfile.println();
hfile.println(" static inline bool IsAlnum(wchar_t c)");
hfile.println(" {");
hfile.println(" return codes[(u2) (blocks[c >> SHIFT] + c)] >= DIGIT_CODE;");
hfile.println(" }");
hfile.println();
hfile.println("};");
hfile.println();
hfile.println("#endif // code_INCLUDED");
printFooter(hfile);
hfile.close();
//
// Process the code.cpp file
//
System.out.println("Generating code.cpp");
PrintStream cfile = new PrintStream(new FileOutputStream("code.cpp"));
printHeader(cfile, new String[] {"\"code.h\""});
cfile.println("char Code::codes[" + bestBlkStr.length() + "] =");
cfile.println("{");
for (int j = 0; j < bestBlkStr.length(); j += 4) {
for (int k = 0; k < 4; k++) {
if (k + j >= bestBlkStr.length()) break;
if (k == 0) cfile.print(" ");
cfile.print(" " + CODE_NAMES[bestBlkStr.charAt(k + j)] + ",");
}
cfile.println();
}
cfile.println("};");
cfile.println();
cfile.println();
cfile.println("//");
cfile.println("// The Blocks vector:");
cfile.println("//");
cfile.println("u2 Code::blocks[" + blocks.length + "] =");
cfile.println("{");
for (int k = 0; k < blocks.length; k += 9) {
for (int i = 0; i < 9; i++) {
if (k + i >= blocks.length) break;
if (i == 0) cfile.print(" ");
cfile.print(" 0x" + Integer.toHexString(blocks[k + i]) + ",");
}
cfile.println();
}
cfile.println("};");
printFooter(cfile);
cfile.close();
//
// Print statistics.
//
System.out.println(
"Total static storage utilization is " + blocks.length * 2 + " bytes for block lookup");
System.out.println(" plus " + bestBlkStr.length() + " bytes for the encodings");
System.out.println(
"The number of unicode characters legal in Java sourcecode is " + numElements);
}
public static void main(String[] args) {
List<MyClass> list = new ArrayList<MyClass>();
list.add(new MyClass("Василий"));
list.add(new MyClass("Павел"));
list.add(new MyClass("Андрей"));
list.add(new MyClass("Андрей"));
list.add(new MyClass("Петр"));
list.add(new MyClass("Анжелика"));
System.out.println("Оригинал");
for (MyClass mc : list) {
System.out.println("Item:" + mc);
}
System.out.println();
// Смешивание
Collections.shuffle(list);
System.out.println("Смешивание");
for (MyClass mc : list) {
System.out.println("Item:" + mc);
}
System.out.println();
// Обратный порядок
Collections.reverse(list);
System.out.println("Обратный порядок");
for (MyClass mc : list) {
System.out.println("Item:" + mc);
}
System.out.println();
// "Проворачивание" на определенное количество
Collections.rotate(list, 2); // Число может быть отрицательным - тогда порядок будет обратный
System.out.println("Проворачивание");
for (MyClass mc : list) {
System.out.println("Item:" + mc);
}
System.out.println();
// Обмен элементов
Collections.swap(list, 0, list.size() - 1);
System.out.println("Обмен элементов");
for (MyClass mc : list) {
System.out.println("Item:" + mc);
}
System.out.println();
// Замена
Collections.replaceAll(list, new MyClass("Андрей"), new MyClass("Алексей"));
System.out.println("Замена");
for (MyClass mc : list) {
System.out.println("Item:" + mc);
}
System.out.println();
// Сортировка
// Collections.sort(list); // Этот запрос не пройдет т.к. класс MyClass
// не реализует интерфейс Comparable
System.out.println("Сортировка Comparable класса");
List<MyClassCompare> listSort = new ArrayList<MyClassCompare>();
System.out.println("Без сортировки");
for (MyClass mc : list) {
listSort.add(new MyClassCompare(mc.toString()));
System.out.println("Item sort:" + mc);
}
Collections.sort(listSort);
System.out.println("После сортировки");
for (MyClassCompare mc : listSort) {
System.out.println("Item sort:" + mc);
}
System.out.println();
// Сортировка с классом Comparator
System.out.println("Сортировка с Comparator");
System.out.println("Без сортировки");
for (MyClass mc : list) {
System.out.println("Item:" + mc);
}
Collections.sort(list, new MyClassComparator());
System.out.println("После сортировки");
for (MyClass mc : list) {
System.out.println("Item:" + mc);
}
System.out.println();
// Копирование - здесь обязательно надо иметь нужные размеры
List<MyClass> list2 = new ArrayList<MyClass>();
// Поэтому заполняем список. Хоть чем-нибудь.
for (MyClass mc : list) {
list2.add(null);
}
// Компируем из правого аргумента в левый
Collections.copy(list2, list);
System.out.println("Копирование");
for (MyClass mc : list2) {
System.out.println("Item:" + mc);
}
System.out.println();
// Полная замена
Collections.fill(list2, new MyClass("Антон"));
System.out.println("Полная замена");
for (MyClass mc : list2) {
System.out.println("Item:" + mc);
}
System.out.println();
}