http://macrochen.iteye.com/blog/737058
參考:
Java代碼 ?
Map<String,?Map<Long,?List<String>>>?map?=?new ?HashMap<String,?Map<Long,List<String>>>();??
Map<String, Map<Long, List<String>>> map = new HashMap<String, Map<Long,List<String>>>();
Java代碼 ?
Map<String,?Map<Long,?List<String>>>?map?=?Maps.newHashMap();??
Map<String, Map<Long, List<String>>> map = Maps.newHashMap();
Java代碼 ?
List<String>?list?=?new ?ArrayList<String>(); ?? list.add("a" ); ?? list.add("b" ); ?? list.add("c" ); ?? list.add("d" );??
List<String> list = new ArrayList<String>();
list.add("a");
list.add("b");
list.add("c");
list.add("d");
Java代碼 ?
ImmutableList<String>?of?=?ImmutableList.of("a" ,?"b" ,?"c" ,?"d" ); ?? ImmutableMap<String,String>?map?=?ImmutableMap.of("key1" ,?"value1" ,?"key2" ,?"value2" );??
ImmutableList<String> of = ImmutableList.of("a", "b", "c", "d");
ImmutableMap<String,String> map = ImmutableMap.of("key1", "value1", "key2", "value2");
Java代碼 ?
File?file?=?new ?File(getClass().getResource("/test.txt" ).getFile()); ?? List<String>?lines?=?null ; ?? try ?{ ??lines?=?Files.readLines(file,?Charsets.UTF_8); ?? }?catch ?(IOException?e)?{ ?? e.printStackTrace(); ?? }??
File file = new File(getClass().getResource("/test.txt").getFile());
List<String> lines = null;
try {
lines = Files.readLines(file, Charsets.UTF_8);
} catch (IOException e) {
e.printStackTrace();
}
Java代碼 ?
int ?compare?=?Ints.compare(a,?b);??
int compare = Ints.compare(a, b);
Java代碼 ?
assertEquals("89983" ,?CharMatcher.DIGIT.retainFrom("some?text?89983?and?more" )) ?? assertEquals("some?text??and?more" ,?CharMatcher.DIGIT.removeFrom("some?text?89983?and?more" ))??
assertEquals("89983", CharMatcher.DIGIT.retainFrom("some text 89983 and more"))
assertEquals("some text and more", CharMatcher.DIGIT.removeFrom("some text 89983 and more"))
Java代碼 ?
int []?numbers?=?{?1 2 3 4 5 String?numbersAsString?=?Joiner.on(";" ).join(Ints.asList(numbers));??
int[] numbers = { 1, 2, 3, 4, 5 };
String numbersAsString = Joiner.on(";").join(Ints.asList(numbers));
Java代碼 ?
String?numbersAsStringDirectly?=?Ints.join(";" ,?numbers);??
String numbersAsStringDirectly = Ints.join(";", numbers);
Java代碼 ?
Iterable?split?=?Splitter.on("," ).split(numbsAsString);??
Iterable split = Splitter.on(",").split(numbsAsString);
Java代碼 ?
String?testString?=?"foo?,?what,,,more," ; ?? Iterable<String>?split?=?Splitter.on("," ).omitEmptyStrings().trimResults().split(testString);??
String testString = "foo , what,,,more,";
Iterable<String> split = Splitter.on(",").omitEmptyStrings().trimResults().split(testString);
Java代碼 ?
int []?array?=?{?1 2 3 4 5 int ?a?=?4 boolean ?contains?=?Ints.contains(array,?a); ??int ?indexOf?=?Ints.indexOf(array,?a); ??int ?max?=?Ints.max(array); ??int ?min?=?Ints.min(array); ??int []?concat?=?Ints.concat(array,?array2);??
int[] array = { 1, 2, 3, 4, 5 };
int a = 4;
boolean contains = Ints.contains(array, a);
int indexOf = Ints.indexOf(array, a);
int max = Ints.max(array);
int min = Ints.min(array);
int[] concat = Ints.concat(array, array2);
Java代碼 ?
HashSet?setA?=?newHashSet(1 2 3 4 5 HashSet?setB?=?newHashSet(4 5 6 7 8 ? ?? SetView?union?=?Sets.union(setA,?setB); ?? System.out.println("union:" ); ?? for ?(Integer?integer?:?union) ??????System.out.println(integer);??????? ?? ? ?? SetView?difference?=?Sets.difference(setA,?setB); ?? System.out.println("difference:" ); ?? for ?(Integer?integer?:?difference) ??????System.out.println(integer);?????? ?? ? ?? SetView?intersection?=?Sets.intersection(setA,?setB); ?? System.out.println("intersection:" ); ?? for ?(Integer?integer?:?intersection) ??????System.out.println(integer);??
HashSet setA = newHashSet(1, 2, 3, 4, 5);
HashSet setB = newHashSet(4, 5, 6, 7, 8);SetView union = Sets.union(setA, setB);
System.out.println("union:");
for (Integer integer : union)System.out.println(integer); SetView difference = Sets.difference(setA, setB);
System.out.println("difference:");
for (Integer integer : difference)System.out.println(integer); SetView intersection = Sets.intersection(setA, setB);
System.out.println("intersection:");
for (Integer integer : intersection)System.out.println(integer);
Java代碼 ?
MapDifference?differenceMap?=?Maps.difference(mapA,?mapB); ?? ?? differenceMap.areEqual(); ?? Map?entriesDiffering?=?differenceMap.entriesDiffering(); ?? Map?entriesOnlyOnLeft?=?differenceMap.entriesOnlyOnLeft(); ?? Map?entriesOnlyOnRight?=?differenceMap.entriesOnlyOnRight(); ?? Map?entriesInCommon?=?differenceMap.entriesInCommon();??
MapDifference differenceMap = Maps.difference(mapA, mapB);differenceMap.areEqual();
Map entriesDiffering = differenceMap.entriesDiffering();
Map entriesOnlyOnLeft = differenceMap.entriesOnlyOnLeft();
Map entriesOnlyOnRight = differenceMap.entriesOnlyOnRight();
Map entriesInCommon = differenceMap.entriesInCommon();
Java代碼 ?
if ?(count?<=?0 ????throw ?new ?IllegalArgumentException("must?be?positive:?" ?+?count);??????? ?? }?? ?? ??????
if (count <= 0) { throw new IllegalArgumentException("must be positive: " + count);
}
???????????
Java代碼 ?
Preconditions.checkArgument(count?>?0 "must?be?positive:?%s" ,?count);??
Preconditions.checkArgument(count > 0, "must be positive: %s", count);
Java代碼 ?
public ?PostExample(final ?String?title,?final ?Date?date,?final ?String?author)?{ ??????this .title?=?checkNotNull(title); ?? ????this .date?=?checkNotNull(date); ?? ????this .author?=?checkNotNull(author); ?? }??
public PostExample(final String title, final Date date, final String author) {this.title = checkNotNull(title);this.date = checkNotNull(date);this.author = checkNotNull(author);
}
Java代碼 ?
Multimap<Person,?BlogPost>?multimap?=?ArrayListMultimap.create();??
Multimap<Person, BlogPost> multimap = ArrayListMultimap.create();
Java代碼 ?
List<Map<String,?String>>?listOfMaps?=?mapOf("type" ,?"blog" ,?"id" ,?"292" ,?"author" ,?"john" );??
List<Map<String, String>> listOfMaps = mapOf("type", "blog", "id", "292", "author", "john");
Java代碼 ?
Multimap<String,?Map<String,?String>>?partitionedMap?=?Multimaps.index(??? ?? ????????????????listOfMaps,??????????????????????????????????????????????????????????????????????????????????????? ?? ????????????????new ?Function<Map<String,?String>,?String>()?{????????????????????????????????? ?? ????????????????????public ?String?apply(final ?Map<String,?String>?from)?{???????????????????? ?? ????????????????????????return ?from.get("type" );????????????????????????????????????????????????????????????? ?? ????????????????????}??????????????????????????????????????????????????????????????????????????????????????????????????? ?? ????????????????});???
Multimap<String, Map<String, String>> partitionedMap = Multimaps.index( listOfMaps, new Function<Map<String, String>, String>() { public String apply(final Map<String, String> from) { return from.get("type"); } });
????????????????????????????????????????????????????????????????????????????????????????????????????
Java代碼 ?
public ?boolean ?equals(Object?o)?{ ????if ?(o?instanceof ?Order)?{ ?? ????Order?that?=?(Order)o; ?? ?? ????return ?Objects.equal(address,?that.address) ?? ????????&&?Objects.equal(targetArrivalDate,?that.targetArrivalDate) ?? ????????&&?Objects.equal(lineItems,?that.lineItems); ?? ??}?else ?{ ?? ????return ?false ; ?? ??} ?? } ?? ?? public ?int ?hashCode()?{ ????return ?Objects.hashCode(address,?targetArrivalDate,?lineItems); ?? }??
public boolean equals(Object o) {if (o instanceof Order) {Order that = (Order)o;return Objects.equal(address, that.address)&& Objects.equal(targetArrivalDate, that.targetArrivalDate)&& Objects.equal(lineItems, that.lineItems);} else {return false;}}public int hashCode() {return Objects.hashCode(address, targetArrivalDate, lineItems);}
Java代碼 ?
public ?Directions(Address?from,?Address?to,?List<Step>?steps)?{ ????this .from?=?from; ?? ??this .to?=?to; ?? ??this .steps?=?Collections.unmodifiableList(new ?ArrayList<Step>(steps)); ?? }??
public Directions(Address from, Address to, List<Step> steps) {this.from = from;this.to = to;this.steps = Collections.unmodifiableList(new ArrayList<Step>(steps));}
Java代碼 ?
public ?Directions(Address?from,?Address?to,?List<Step>?steps)?{ ????this .from?=?from; ?? ??this .to?=?to; ?? ??this .steps?=?ImmutableList.of(steps); ?? }??
public Directions(Address from, Address to, List<Step> steps) {this.from = from;this.to = to;this.steps = ImmutableList.of(steps);}
Java代碼 ?
public ?boolean ?orderContains(Product?product)?{ ????List<LineItem>?allLineItems?=?new ?ArrayList<LineItem>(); ?? ??allLineItems.addAll(getPurchasedItems()); ?? ??allLineItems.addAll(getFreeItems()); ?? ?? ??for ?(LineItem?lineItem?:?allLineItems)?{ ?? ????if ?(lineItem.getProduct()?==?product)?{ ?? ??????return ?true ; ?? ????} ?? ??} ?? ?? ??return ?false ; ?? }??
public boolean orderContains(Product product) {List<LineItem> allLineItems = new ArrayList<LineItem>();allLineItems.addAll(getPurchasedItems());allLineItems.addAll(getFreeItems());for (LineItem lineItem : allLineItems) {if (lineItem.getProduct() == product) {return true;}}return false;}
Java代碼 ?
public ?boolean ?orderContains(Product?product)?{ ????for ?(LineItem?lineItem?:?Iterables.concat(getPurchasedItems(),?getFreeItems()))?{ ?? ????if ?(lineItem.getProduct()?==?product)?{ ?? ??????return ?true ; ?? ????} ?? ??} ?? ?? ??return ?false ; ?? }??
public boolean orderContains(Product product) {for (LineItem lineItem : Iterables.concat(getPurchasedItems(), getFreeItems())) {if (lineItem.getProduct() == product) {return true;}}return false;}
Java代碼 ?
private ?final ?List<LineItem>?purchases?=?new ?ArrayList<LineItem>(); ???? ? ? ? ?? public ?List<LineItem>?getPurchases()?{ ????return ?Collections.unmodifiableList(purchases); ?? } ?? ?? public ?void ?addPurchase(LineItem?purchase)?{ ????Preconditions.checkState(catalog.isOffered(getAddress(),?purchase.getProduct())); ?? ??Preconditions.checkState(purchase.getCharge().getUnits()?>?0 ??purchases.add(purchase); ?? } ?? 這么寫: ?? private ?final ?List<LineItem>?purchases?=?Constraints.constrainedList( ??????new ?ArrayList<LineItem>(), ?? ????new ?Constraint<LineItem>()?{ ?? ??????public ?void ?checkElement(LineItem?element)?{ ?? ????????Preconditions.checkState(catalog.isOffered(getAddress(),?element.getProduct())); ?? ????????Preconditions.checkState(element.getCharge().getUnits()?>?0 ??????} ?? ????}); ?? ?? ? ? ?? public ?List<LineItem>?getPurchases()?{ ????return ?purchases; ?? }??
private final List<LineItem> purchases = new ArrayList<LineItem>();/*** Don't modify this! Instead, call {@link #addPurchase(LineItem)} to add* new purchases to this order.*/public List<LineItem> getPurchases() {return Collections.unmodifiableList(purchases);}public void addPurchase(LineItem purchase) {Preconditions.checkState(catalog.isOffered(getAddress(), purchase.getProduct()));Preconditions.checkState(purchase.getCharge().getUnits() > 0);purchases.add(purchase);}
現在這么寫:private final List<LineItem> purchases = Constraints.constrainedList(new ArrayList<LineItem>(),new Constraint<LineItem>() {public void checkElement(LineItem element) {Preconditions.checkState(catalog.isOffered(getAddress(), element.getProduct()));Preconditions.checkState(element.getCharge().getUnits() > 0);}});/*** Returns the modifiable list of purchases in this order.*/public List<LineItem> getPurchases() {return purchases;}
Java代碼 ?
Set<String>?set?=?Sets.newHashSet(); ?? Set<String>?constrainedSet?=?Constraints.constrainedSet(set,?Constraints.notNull()); ?? constrainedSet.add("A" ); ?? constrainedSet.add(null );???
Set<String> set = Sets.newHashSet();Set<String> constrainedSet = Constraints.constrainedSet(set, Constraints.notNull());constrainedSet.add("A");constrainedSet.add(null); // NullPointerException here
Java代碼 ?
Map<Salesperson,?List<Sale>>?map?=?new ?Hashmap<SalesPerson,?List<Sale>>(); ?? ?? public ?void ?makeSale(Salesperson?salesPerson,?Sale?sale)?{ ????List<Sale>?sales?=?map.get(salesPerson); ?? ??if ?(sales?==?null )?{ ?? ????sales?=?new ?ArrayList<Sale>(); ?? ????map.put(salesPerson,?sales); ?? ??} ?? ??sales.add(sale); ?? }??
Map<Salesperson, List<Sale>> map = new Hashmap<SalesPerson, List<Sale>>();public void makeSale(Salesperson salesPerson, Sale sale) {List<Sale> sales = map.get(salesPerson);if (sales == null) {sales = new ArrayList<Sale>();map.put(salesPerson, sales);}sales.add(sale);}
Java代碼 ?
Multimap<Salesperson,?Sale>?multimap? ?? ????=?new ?ArrayListMultimap<Salesperson,Sale>(); ?? ?? public ?void ?makeSale(Salesperson?salesPerson,?Sale?sale)?{ ????multimap.put(salesperson,?sale); ?? }??
Multimap<Salesperson, Sale> multimap = new ArrayListMultimap<Salesperson,Sale>();public void makeSale(Salesperson salesPerson, Sale sale) {multimap.put(salesperson, sale);}
Java代碼 ?
public ?Sale?getBiggestSale()?{ ????Sale?biggestSale?=?null ; ?? ??for ?(List<Sale>?sales?:?map.values())?{ ?? ????Sale?biggestSaleForSalesman ?? ????????=?Collections.max(sales,?SALE_COST_COMPARATOR); ?? ????if ?(biggestSale?==?null ?? ????????||?biggestSaleForSalesman.getCharge()?>?biggestSale().getCharge())?{ ?? ??????biggestSale?=?biggestSaleForSalesman; ?? ????} ?? ??} ?? ??return ?biggestSale; ?? }??
public Sale getBiggestSale() {Sale biggestSale = null;for (List<Sale> sales : map.values()) {Sale biggestSaleForSalesman= Collections.max(sales, SALE_COST_COMPARATOR);if (biggestSale == null|| biggestSaleForSalesman.getCharge() > biggestSale().getCharge()) {biggestSale = biggestSaleForSalesman;}}return biggestSale;}
Java代碼 ?
public ?Sale?getBiggestSale()?{ ????return ?Collections.max(multimap.values(),?SALE_COST_COMPARATOR); ?? }??
public Sale getBiggestSale() {return Collections.max(multimap.values(), SALE_COST_COMPARATOR);}
Java代碼 ?
public ?class ?ShoppingList?{ ????private ?List<Item>?items?=?...; ?? ?? ??... ?? ?? ??public ?String?toString()?{ ?? ????StringBuilder?stringBuilder?=?new ?StringBuilder(); ?? ????for ?(Iterator<Item>?s?=?items.iterator();?s.hasNext();?)?{ ?? ??????stringBuilder.append(s.next()); ?? ??????if ?(s.hasNext())?{ ?? ????????stringBuilder.append("?and?" ); ?? ??????} ?? ????} ?? ????return ?stringBuilder.toString(); ?? ??} ?? }??
public class ShoppingList {private List<Item> items = ...;...public String toString() {StringBuilder stringBuilder = new StringBuilder();for (Iterator<Item> s = items.iterator(); s.hasNext(); ) {stringBuilder.append(s.next());if (s.hasNext()) {stringBuilder.append(" and ");}}return stringBuilder.toString();}
}
Java代碼 ?
public ?class ?ShoppingList?{ ???private ?List<Item>?items?=?...; ?? ?? ?... ?? ?? ?public ?String?toString()?{ ?? ???return ?Join.join("?and?" ,?items); ?? ?} ?? }??
public class ShoppingList {private List<Item> items = ...;...public String toString() {return Join.join(" and ", items);}
}
Java代碼 ?
public ?Comparator<Product>?createRetailPriceComparator( ??????final ?CurrencyConverter?currencyConverter)?{ ?? ??return ?new ?Comparator<Product>()?{ ?? ????public ?int ?compare(Product?a,?Product?b)?{ ?? ??????return ?getRetailPriceInUsd(a).compareTo(getRetailPriceInUsd(b)); ?? ????} ?? ????public ?Money?getRetailPriceInUsd(Product?product)?{ ?? ??????Money?retailPrice?=?product.getRetailPrice(); ?? ??????return ?retailPrice.getCurrency()?==?CurrencyCode.USD ?? ????????????retailPrice ?? ??????????:?currencyConverter.convert(retailPrice,?CurrencyCode.USD); ?? ????} ?? ??}; ?? }??
public Comparator<Product> createRetailPriceComparator(final CurrencyConverter currencyConverter) {return new Comparator<Product>() {public int compare(Product a, Product b) {return getRetailPriceInUsd(a).compareTo(getRetailPriceInUsd(b));}public Money getRetailPriceInUsd(Product product) {Money retailPrice = product.getRetailPrice();return retailPrice.getCurrency() == CurrencyCode.USD? retailPrice: currencyConverter.convert(retailPrice, CurrencyCode.USD);}};}
Java代碼 ?
public ?Comparator<Product>?createRetailPriceComparator( ??????final ?CurrencyConverter?currencyConverter)?{ ?? ??return ?Comparators.fromFunction(new ?Function<Product,Money>()?{ ?? ?????? ????public ?Money?apply(Product?product)?{ ?? ??????Money?retailPrice?=?product.getRetailPrice(); ?? ??????return ?retailPrice.getCurrency()?==?CurrencyCode.USD ?? ????????????retailPrice ?? ??????????:?currencyConverter.convert(retailPrice,?CurrencyCode.USD); ?? ????} ?? ??}); ?? }??
public Comparator<Product> createRetailPriceComparator(final CurrencyConverter currencyConverter) {return Comparators.fromFunction(new Function<Product,Money>() {/** returns the retail price in USD */public Money apply(Product product) {Money retailPrice = product.getRetailPrice();return retailPrice.getCurrency() == CurrencyCode.USD? retailPrice: currencyConverter.convert(retailPrice, CurrencyCode.USD);}});}
Java代碼 ?
private ?static ?final ?Map<Integer,?String>?NUMBER_TO_NAME; ??private ?static ?final ?Map<String,?Integer>?NAME_TO_NUMBER; ???? static ?{ ????NUMBER_TO_NAME?=?Maps.newHashMap(); ?? ??NUMBER_TO_NAME.put(1 "Hydrogen" ); ?? ??NUMBER_TO_NAME.put(2 "Helium" ); ?? ??NUMBER_TO_NAME.put(3 "Lithium" ); ?? ?? ?? ???? ??NAME_TO_NUMBER?=?Maps.newHashMap(); ?? ??for ?(Integer?number?:?NUMBER_TO_NAME.keySet())?{ ?? ????NAME_TO_NUMBER.put(NUMBER_TO_NAME.get(number),?number); ?? ??} ?? } ?? ?? public ?static ?int ?getElementNumber(String?elementName)?{ ????return ?NUMBER_TO_NAME.get(elementName); ?? } ?? ?? public ?static ?string?getElementName(int ?elementNumber)?{ ????return ?NAME_TO_NUMBER.get(elementNumber); ?? }??
private static final Map<Integer, String> NUMBER_TO_NAME;private static final Map<String, Integer> NAME_TO_NUMBER;static {NUMBER_TO_NAME = Maps.newHashMap();NUMBER_TO_NAME.put(1, "Hydrogen");NUMBER_TO_NAME.put(2, "Helium");NUMBER_TO_NAME.put(3, "Lithium");/* reverse the map programatically so the actual mapping is not repeated */NAME_TO_NUMBER = Maps.newHashMap();for (Integer number : NUMBER_TO_NAME.keySet()) {NAME_TO_NUMBER.put(NUMBER_TO_NAME.get(number), number);}}public static int getElementNumber(String elementName) {return NUMBER_TO_NAME.get(elementName);}public static string getElementName(int elementNumber) {return NAME_TO_NUMBER.get(elementNumber);}
Java代碼 ?
private ?static ?final ?BiMap<Integer,String>?NUMBER_TO_NAME_BIMAP; ???? static ?{ ????NUMBER_TO_NAME_BIMAP?=?Maps.newHashBiMap(); ?? ??NUMBER_TO_NAME_BIMAP.put(1 "Hydrogen" ); ?? ??NUMBER_TO_NAME_BIMAP.put(2 "Helium" ); ?? ??NUMBER_TO_NAME_BIMAP.put(3 "Lithium" ); ?? } ?? ?? public ?static ?int ?getElementNumber(String?elementName)?{ ????return ?NUMBER_TO_NAME_BIMAP.inverse().get(elementName); ?? } ?? ?? public ?static ?string?getElementName(int ?elementNumber)?{ ????return ?NUMBER_TO_NAME_BIMAP.get(elementNumber); ?? }??
private static final BiMap<Integer,String> NUMBER_TO_NAME_BIMAP;static {NUMBER_TO_NAME_BIMAP = Maps.newHashBiMap();NUMBER_TO_NAME_BIMAP.put(1, "Hydrogen");NUMBER_TO_NAME_BIMAP.put(2, "Helium");NUMBER_TO_NAME_BIMAP.put(3, "Lithium");}public static int getElementNumber(String elementName) {return NUMBER_TO_NAME_BIMAP.inverse().get(elementName);}public static string getElementName(int elementNumber) {return NUMBER_TO_NAME_BIMAP.get(elementNumber);}
Java代碼 ?
private ?static ?final ?BiMap<Integer,String>?NUMBER_TO_NAME_BIMAP ????=?new ?ImmutableBiMapBuilder<Integer,String>() ?? ??????.put(1 "Hydrogen" ) ?? ??????.put(2 "Helium" ) ?? ??????.put(3 "Lithium" ) ?? ??????.getBiMap();??
private static final BiMap<Integer,String> NUMBER_TO_NAME_BIMAP= new ImmutableBiMapBuilder<Integer,String>().put(1, "Hydrogen").put(2, "Helium").put(3, "Lithium").getBiMap();
Java代碼 ?
assertEquals("test" ,?Strings.emptyToNull("test" )); ?? assertEquals("?" ,?Strings.emptyToNull("?" )); ?? assertNull(Strings.emptyToNull("" )); ?? assertNull(Strings.emptyToNull(null )); ?? ? ?? assertFalse(Strings.isNullOrEmpty("test" )); ?? assertFalse(Strings.isNullOrEmpty("?" )); ?? assertTrue(Strings.isNullOrEmpty("" )); ?? assertTrue(Strings.isNullOrEmpty(null )); ?? ? ?? assertEquals("test" ,?Strings.nullToEmpty("test" )); ?? assertEquals("?" ,?Strings.nullToEmpty("?" )); ?? assertEquals("" ,?Strings.nullToEmpty("" )); ?? assertEquals("" ,?Strings.nullToEmpty(null )); ?? ? ?? assertEquals("Ralph_____" ,?Strings.padEnd("Ralph" ,?10 '_' )); ?? assertEquals("Bob_______" ,?Strings.padEnd("Bob" ,?10 '_' )); ?? ? ?? assertEquals("_____Ralph" ,?Strings.padStart("Ralph" ,?10 '_' )); ?? assertEquals("_______Bob" ,?Strings.padStart("Bob" ,?10 '_' )); ?? ?? assertEquals("xyxyxyxyxy" ,?Strings.repeat("xy" ,?5
assertEquals("test", Strings.emptyToNull("test"));
assertEquals(" ", Strings.emptyToNull(" "));
assertNull(Strings.emptyToNull(""));
assertNull(Strings.emptyToNull(null));assertFalse(Strings.isNullOrEmpty("test"));
assertFalse(Strings.isNullOrEmpty(" "));
assertTrue(Strings.isNullOrEmpty(""));
assertTrue(Strings.isNullOrEmpty(null));assertEquals("test", Strings.nullToEmpty("test"));
assertEquals(" ", Strings.nullToEmpty(" "));
assertEquals("", Strings.nullToEmpty(""));
assertEquals("", Strings.nullToEmpty(null));assertEquals("Ralph_____", Strings.padEnd("Ralph", 10, '_'));
assertEquals("Bob_______", Strings.padEnd("Bob", 10, '_'));assertEquals("_____Ralph", Strings.padStart("Ralph", 10, '_'));
assertEquals("_______Bob", Strings.padStart("Bob", 10, '_'));assertEquals("xyxyxyxyxy", Strings.repeat("xy", 5));
Java代碼 ?
package ?com.ociweb.jnb.apr2010; ???? import ?com.google.common.base.Throwables; ???? import ?java.io.InputStream; ??import ?java.net.URL; ???? public ?class ?ExerciseThrowables?{ ??????public ?static ?void ?main(String[]?args)?{ ?? ????????try ?{ ?? ????????????URL?url?=?new ?URL("http://ociweb.com" ); ?? ????????????final ?InputStream?in?=?url.openStream(); ?? ???????????? ?? ????????????in.close(); ?? ????????}?catch ?(Throwable?t)?{ ?? ????????????throw ?Throwables.propagate(t); ?? ????????} ?? ????} ?? }??
package com.ociweb.jnb.apr2010;import com.google.common.base.Throwables;import java.io.InputStream;
import java.net.URL;public class ExerciseThrowables {public static void main(String[] args) {try {URL url = new URL("http://ociweb.com");final InputStream in = url.openStream();// read from the input streamin.close();} catch (Throwable t) {throw Throwables.propagate(t);}}
}
Java代碼 ?
Multimap<Integer,?String>?siblings?=?Multimaps.newHashMultimap(); ?? siblings.put(0 "Kenneth" ); ?? siblings.put(1 "Joe" ); ?? siblings.put(2 "John" ); ?? siblings.put(3 "Jerry" ); ?? siblings.put(3 "Jay" ); ?? siblings.put(5 "Janet" ); ?? ?? for ?(int ?i?=?0 6 ????int ?freq?=?siblings.get(i).size(); ?? ????System.out.printf("%d?siblings?frequency?%d\n" ,?i,?freq); ?? }??
Multimap<Integer, String> siblings = Multimaps.newHashMultimap();siblings.put(0, "Kenneth");siblings.put(1, "Joe");siblings.put(2, "John");siblings.put(3, "Jerry");siblings.put(3, "Jay");siblings.put(5, "Janet");for (int i = 0; i < 6; i++) {int freq = siblings.get(i).size();System.out.printf("%d siblings frequency %d\n", i, freq);}
引用
0 siblings frequency 1
??????? 1 siblings frequency 1
??????? 2 siblings frequency 1
??????? 3 siblings frequency 2
??????? 4 siblings frequency 0
??????? 5 siblings frequency 1
Java代碼 ?
Function<String,?Integer>?strlen?=?new ?Function<String,?Integer>()?{ ?? ????public ?Integer?apply(String?from)?{ ?? ????????Preconditions.checkNotNull(from); ?? ????????return ?from.length(); ?? ????} ?? }; ?? List<String>?from?=?Lists.newArrayList("abc" ,?"defg" ,?"hijkl" ); ?? List<Integer>?to?=?Lists.transform(from,?strlen); ?? for ?(int ?i?=?0 ????System.out.printf("%s?has?length?%d\n" ,?from.get(i),?to.get(i)); ?? } ??
Function<String, Integer> strlen = new Function<String, Integer>() {public Integer apply(String from) {Preconditions.checkNotNull(from);return from.length();}};List<String> from = Lists.newArrayList("abc", "defg", "hijkl");List<Integer> to = Lists.transform(from, strlen);for (int i = 0; i < from.size(); i++) {System.out.printf("%s has length %d\n", from.get(i), to.get(i));}}
Java代碼 ?
Function<String,?Boolean>?isPalindrome?=?new ?Function<String,?Boolean>()?{ ?? ????public ?Boolean?apply(String?from)?{ ?? ????????Preconditions.checkNotNull(from); ?? ????????return ?new ?StringBuilder(from).reverse().toString().equals(from); ?? ????} ?? }; ?? List<String>?from?=?Lists.newArrayList("rotor" ,?"radar" ,?"hannah" ,?"level" ,?"botox" ); ?? List<Boolean>?to?=?Lists.transform(from,?isPalindrome); ?? for ?(int ?i?=?0 ????System.out.printf("%s?is%sa?palindrome\n" ,?from.get(i),?to.get(i)???"?" ?:?"?NOT?" ); ?? }? ?? ?? System.out.printf("\nnow?replace?hannah?with?megan...\n\n" ); ?? from.set(2 "megan" ); ?? for ?(int ?i?=?0 ????System.out.printf("%s?is%sa?palindrome\n" ,?from.get(i),?to.get(i)???"?" ?:?"?NOT?" ); ?? } ??
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總結
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