-
Notifications
You must be signed in to change notification settings - Fork 2k
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Merge pull request #862 from anuchandy/pagedvmimages
Lazy load the virtual machine image list
- Loading branch information
Showing
14 changed files
with
327 additions
and
70 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
8 changes: 8 additions & 0 deletions
8
...mpute/src/main/java/com/microsoft/azure/management/compute/VirtualMachineImagesInSku.java
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,8 @@ | ||
| package com.microsoft.azure.management.compute; | ||
| import com.microsoft.azure.management.resources.fluentcore.collection.SupportsListing; | ||
|
|
||
| /** | ||
| * Entry point to virtual machine sku images. | ||
| */ | ||
| public interface VirtualMachineImagesInSku extends SupportsListing<VirtualMachineImage> { | ||
| } |
181 changes: 181 additions & 0 deletions
181
...c/main/java/com/microsoft/azure/management/compute/implementation/ChildListFlattener.java
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,181 @@ | ||
| package com.microsoft.azure.management.compute.implementation; | ||
|
|
||
| import com.microsoft.azure.CloudException; | ||
| import com.microsoft.azure.Page; | ||
| import com.microsoft.azure.PagedList; | ||
| import com.microsoft.rest.RestException; | ||
|
|
||
| import java.io.IOException; | ||
| import java.util.Iterator; | ||
| import java.util.List; | ||
|
|
||
| /** | ||
| * {@link ChildListFlattener} that can take a paged list of parents and flatten their child lists | ||
| * as a single lazy paged list. | ||
| * | ||
| * @param <ParentT> the type of parent paged list item | ||
| * @param <ChildT> the type of child paged list item | ||
| */ | ||
| final class ChildListFlattener<ParentT, ChildT> { | ||
| protected final String switchToCousin = "switchToCousin"; | ||
| protected Iterator<ParentT> parentItr; | ||
| protected PagedList<ChildT> currentChildList; | ||
| protected PagedList<ChildT> cousinList; | ||
| private final ChildListLoader<ParentT, ChildT> childListLoader; | ||
|
|
||
| /** | ||
| * Interface that will be implemented by the consumer of {@link ChildListFlattener}. | ||
| * <p> | ||
| * implementation will be used by {@link ChildListFlattener#flatten()} to load child | ||
| * paged list of parents in the parent paged list. | ||
| * | ||
| * @param <T> the parent type | ||
| * @param <U> the type of items in the child list | ||
| */ | ||
| interface ChildListLoader<T, U> { | ||
| /** | ||
| * Get the child paged list associated with the given parent. | ||
| * | ||
| * @param parent the parent | ||
| * @return child paged list associated with the parent | ||
| * @throws CloudException exceptions thrown from the cloud | ||
| * @throws IOException exceptions thrown from serialization/deserialization | ||
| */ | ||
| PagedList<U> loadList(T parent) throws CloudException, IOException; | ||
| } | ||
|
|
||
| /** | ||
| * Creates ChildListFlattener. | ||
| * | ||
| * @param parentList a paged list of parents | ||
| * @param childListLoader {@link ChildListLoader} for fetching child paged list associated any parent | ||
| */ | ||
| ChildListFlattener(PagedList<ParentT> parentList, ChildListLoader<ParentT, ChildT> childListLoader) { | ||
| this.parentItr = parentList.iterator(); | ||
| this.childListLoader = childListLoader; | ||
| } | ||
|
|
||
| /** | ||
| * flatten the child paged lists. | ||
| * | ||
| * @return the lazy flattened paged list from the child paged lists | ||
| * @throws CloudException exceptions thrown from the cloud | ||
| * @throws IOException exceptions thrown from serialization/deserialization | ||
| */ | ||
| public PagedList<ChildT> flatten() throws CloudException, IOException { | ||
| this.currentChildList = nextChildList(); | ||
| if (this.currentChildList == null) { | ||
| return emptyPagedList(); | ||
| } | ||
| // setCousin sets the next child paged list (i.e. the current child list's immediate cousin). | ||
| // we need to know in advance whether there is going to be a next child paged list (cousin). | ||
| // This is because the 'next link' of the current child paged list's last page will be null. | ||
| // when the PagedList sees next link as null it assumes there is no more pages hence it won't | ||
| // call nextPage and iteration stops, if cousin presents then 'childListPage' method replace | ||
| // this null with a marker indicating there is more pages. | ||
| setCousin(); | ||
| return new PagedList<ChildT>(childListPage(currentChildList.currentPage())) { | ||
| @Override | ||
| public Page<ChildT> nextPage(String nextPageLink) throws RestException, IOException { | ||
| if (nextPageLink.equalsIgnoreCase(switchToCousin)) { | ||
| // Reached end of current child paged list, make next child list(cousin) as current | ||
| // paged list and return it's first page. | ||
| currentChildList = cousinList; | ||
| setCousin(); | ||
| return childListPage(currentChildList.currentPage()); | ||
| } else { | ||
| currentChildList.loadNextPage(); | ||
| if (currentChildList.currentPage().getNextPageLink() == null) { | ||
| // This is the last page of the current child paged list set it's cousin | ||
| // so that next call to nextPage can start using it. | ||
| setCousin(); | ||
| } | ||
| return childListPage(currentChildList.currentPage()); | ||
| } | ||
| } | ||
| }; | ||
| } | ||
|
|
||
| /** | ||
| * @return true if the current child paged list has a cousin | ||
| */ | ||
| private boolean hasCousin() { | ||
| return this.cousinList != null; | ||
| } | ||
|
|
||
| /** | ||
| * Locate and sets the cousin list (the next child paged list). | ||
| * | ||
| * @throws CloudException exceptions thrown from the cloud | ||
| * @throws IOException exceptions thrown from serialization/deserialization | ||
| */ | ||
| private void setCousin() throws CloudException, IOException { | ||
| cousinList = nextChildList(); | ||
| } | ||
|
|
||
| /** | ||
| * Returns the next child paged list containing at least one item. | ||
| * <p> | ||
| * This method iterate the parent list from where it stopped last time and return | ||
| * a non-empty child paged list of a parent. If there is no parent with non-empty child list | ||
| * or if the parent list iteration is finished then this method returns null. | ||
| * | ||
| * @return a child paged list {@link PagedList} | ||
| * @throws CloudException exceptions thrown from the cloud | ||
| * @throws IOException exceptions thrown from serialization/deserialization | ||
| */ | ||
| private PagedList<ChildT> nextChildList() throws CloudException, IOException { | ||
| while (parentItr.hasNext()) { | ||
| PagedList<ChildT> nextChildList = childListLoader.loadList(parentItr.next()); | ||
| if (nextChildList.iterator().hasNext()) { | ||
| return nextChildList; | ||
| } | ||
| } | ||
| return null; | ||
| } | ||
|
|
||
| /** | ||
| * Method returns a {@link Page} with the same items as in the given page, if the given | ||
| * page is last page of the current paged child list and if there is a cousin list then | ||
| * returned page's next-link will be set to a predefined value indicating presence of | ||
| * cousin list. | ||
| * | ||
| * @param page the page | ||
| * @return page with next-link updated if there is a cousin | ||
| */ | ||
| private Page<ChildT> childListPage(final Page<ChildT> page) { | ||
| return new Page<ChildT>() { | ||
| @Override | ||
| public String getNextPageLink() { | ||
| if (page.getNextPageLink() != null) { | ||
| // The current child paged list has more pages. | ||
| return page.getNextPageLink(); | ||
| } | ||
|
|
||
| if (hasCousin()) { | ||
| // The current child paged list has no more pages so switch to it's cousin list | ||
| return switchToCousin; | ||
| } | ||
| // reached end of child paged list of last parent, iteration will be stopped. | ||
| return null; | ||
| } | ||
|
|
||
| @Override | ||
| public List<ChildT> getItems() { | ||
| return page.getItems(); | ||
| } | ||
| }; | ||
| } | ||
|
|
||
| /** | ||
| * @return an empty paged list | ||
| */ | ||
| private PagedList<ChildT> emptyPagedList() { | ||
| return new PagedList<ChildT>() { | ||
| @Override | ||
| public Page<ChildT> nextPage(String nextPageLink) throws RestException, IOException { | ||
| return null; | ||
| } | ||
| }; | ||
| } | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Oops, something went wrong.