diff options
Diffstat (limited to 'demos/java/gsviewer/src/com/artifex/gsviewer/Document.java')
| -rw-r--r-- | demos/java/gsviewer/src/com/artifex/gsviewer/Document.java | 335 |
1 files changed, 245 insertions, 90 deletions
diff --git a/demos/java/gsviewer/src/com/artifex/gsviewer/Document.java b/demos/java/gsviewer/src/com/artifex/gsviewer/Document.java index 1f0deda68..c32b49514 100644 --- a/demos/java/gsviewer/src/com/artifex/gsviewer/Document.java +++ b/demos/java/gsviewer/src/com/artifex/gsviewer/Document.java @@ -12,9 +12,7 @@ import java.util.LinkedList; import java.util.List; import java.util.ListIterator; import java.util.Objects; -import java.util.concurrent.atomic.AtomicBoolean; import java.util.concurrent.locks.Condition; -import java.util.concurrent.locks.Lock; import java.util.concurrent.locks.ReentrantLock; import com.artifex.gsjava.callbacks.DisplayCallback; @@ -23,23 +21,47 @@ import com.artifex.gsjava.util.LongReference; import com.artifex.gsviewer.ImageUtil.ImageParams; /** - * A Document stores an ordered list of Pages. + * <p>A Document stores an ordered list of Pages. This class implements + * <code>java.util.List</code>, so it inherits all of a list's capabilities, + * such as the ability to iterate over the document.</p> + * + * <p>The Document class also handles loading of pages through Ghostcript + * and ensuring that two Ghostscript operations are not running at the + * same time.</p> * * @author Ethan Vrhel * */ public class Document implements List<Page> { - private static final Object slock = new Object(); - private static final DocumentLoader documentLoader = new DocumentLoader(); - private static final int format = GS_COLORS_RGB | GS_DISPLAY_DEPTH_8 | GS_DISPLAY_BIGENDIAN; + private static final DocumentLoader documentLoader = new DocumentLoader(); // The document loader + private static final int format = GS_COLORS_RGB | GS_DISPLAY_DEPTH_8 | GS_DISPLAY_BIGENDIAN; // Format - private static final ReentrantLock operationLock = new ReentrantLock(); - private static final Condition operationCv = operationLock.newCondition(); - private static final AtomicBoolean operationInProgress = new AtomicBoolean(false); + private static final ReentrantLock operationLock = new ReentrantLock(); // The operation lock + private static final Condition operationCv = operationLock.newCondition(); // The operation condition variable + private static volatile boolean operationInProgress = false; // Whether an operation is in progress + /** + * Asynchronous execution dispatch returns. + */ public static final int ASYNC_DISPATCH_OK = 0, ASYNC_DISPATCH_OPERATION_IN_PROGRESS = 1; - public static final int OPERATION_WAIT = 0, OPERATION_RETURN = 1, OPERATION_THROW = 2; + + /** + * Operation mode indicating the method should wait until a running operation has finished. + */ + public static final int OPERATION_WAIT = 0; + + /** + * Operation mode indicating the method should immediately return if an operation is already + * running. + */ + public static final int OPERATION_RETURN = 1; + + /** + * Operation mode indicating the method should throw an <code>OperationInProgressException</code> + * if an operation is already running. + */ + public static final int OPERATION_THROW = 2; /** * Loads a document on a separate thread. @@ -175,24 +197,41 @@ public class Document implements List<Page> { return loadDocumentAsync(filename, cb, null, operationMode); } + /** + * Call, internally, on the start of an operation. + */ private static void startOperation() { - operationInProgress.set(true); + operationInProgress = true; } + /** + * Call, internally, on the start of an operation, before <code>startOperation()</code>. + * + * @param operationMode The operation mode. + * @return Whether the calling function should continue to its operation. + * @throws OperationInProgressException When an operation is in progress and <code>operationMode</code> + * is <code>OPERATION_THROW</code>. This should not be caught by the calling function, who should + * throw it instead. + * @throws IllegalArgumentException When <code>operationMode</code> is not a valid operation mode. + */ private static boolean handleOperationMode(final int operationMode) throws OperationInProgressException, IllegalArgumentException { - boolean inProgress = operationInProgress.get(); - if (inProgress && operationMode == OPERATION_RETURN) + if (operationInProgress && operationMode == OPERATION_RETURN) return false; - else if (inProgress && operationMode == OPERATION_THROW) - throw new OperationInProgressException("loadDocument"); - else if (inProgress && operationMode == OPERATION_WAIT) + else if (operationInProgress && operationMode == OPERATION_THROW) { + StackTraceElement[] elems = new Exception().getStackTrace(); + throw new OperationInProgressException(elems[1].getClassName() + "." + elems[1].getMethodName()); + } else if (operationInProgress && operationMode == OPERATION_WAIT) waitForOperation(); - else if (inProgress) + else if (operationInProgress) throw new IllegalArgumentException("Unknown operation mode: " + operationMode); return true; } + /** + * Called internally by <code>handleOperationMode()</code>. Waits for an operation + * to finish. + */ private static void waitForOperation() { operationLock.lock(); try { @@ -204,11 +243,14 @@ public class Document implements List<Page> { } } + /** + * Call, internally, when an operation is done. + */ private static void operationDone() { operationLock.lock(); - operationInProgress.set(false); + operationInProgress = false; try { - operationCv.notify(); + operationCv.signal(); } finally { operationLock.unlock(); } @@ -255,6 +297,12 @@ public class Document implements List<Page> { } } + /** + * Initializes an instance of Ghostcript. + * + * @param instanceRef A reference to the instance of Ghostscript. + * @throws IllegalStateException When any Ghostscript operation fails to execute. + */ private static void initDocInstance(LongReference instanceRef) throws IllegalStateException { int code = gsapi_new_instance(instanceRef, GS_NULL); if (code != GS_ERROR_OK) { @@ -275,6 +323,12 @@ public class Document implements List<Page> { } } + /** + * Class which handles loading a Document. + * + * @author Ethan Vrhel + * + */ private static class DocumentLoader extends DisplayCallback { private int pageWidth, pageHeight, pageRaster; private BytePointer pimage; @@ -337,9 +391,10 @@ public class Document implements List<Page> { * @throws FileNotFoundException When <code>file</code> does not exist. * @throws IllegalStateException When Ghostscript fails to initialize or load the document. * @throws NullPointerException When <code>file</code> is <code>null</code>. - * @throws OperationInProgressException When an operation is already in progress. + * @throws OperationInProgressException When an operation is already in progress + * and <code>operationMode</code> is <code>OPERATION_THROW</code>. * @throws IllegalArgumentException When <code>operationMode</code> is not - * <code>ASYNC_OPERTAION_WAIT</coded> or <code>ASYNC_OPERATION_RETURN</code>. + * <code>OPERATION_WAIT</coded>, <code>OPERATION_RETURN</code>, or <code>OPERATION_THROW</code>. */ public Document(final File file, final DocLoadProgressCallback loadCallback, int operationMode) throws FileNotFoundException, IllegalStateException, NullPointerException, @@ -388,11 +443,19 @@ public class Document implements List<Page> { * Creates and loads a document from a filename. * * @param file The file to load. + * @param operationMode How the loader should behave if an operation is already in + * progress. Can be <code>OPERATION_WAIT</code>, meaning the loader should + * wait until a running operation has finished, <code>OPERATION_RETURN</code> meaning + * the loader should immediately return, or <code>OPERATION_THROW</code> meaning the loader + * should throw an <code>OperationInProgressException</code>. * * @throws FileNotFoundException When <code>file</code> does not exist. * @throws IllegalStateException When Ghostscript fails to initialize or load the document. * @throws NullPointerException When <code>file</code> is <code>null</code>. - * @throws OperationInProgressException When an operation is already in progress. + * @throws OperationInProgressException When an operation is already in progress + * and <code>operationMode</code> is <code>OPERATION_THROW</code>. + * @throws IllegalArgumentException When <code>operationMode</code> is not + * <code>OPERATION_WAIT</coded>, <code>OPERATION_RETURN</code>, or <code>OPERATION_THROW</code>. */ public Document(final File file, final int operationMode) throws FileNotFoundException, IllegalStateException, NullPointerException, @@ -405,11 +468,19 @@ public class Document implements List<Page> { * * @param filename The name of the file to load. * @param loadCallback The callback to indicate when progress has occurred while loading. + * @param operationMode How the loader should behave if an operation is already in + * progress. Can be <code>OPERATION_WAIT</code>, meaning the loader should + * wait until a running operation has finished, <code>OPERATION_RETURN</code> meaning + * the loader should immediately return, or <code>OPERATION_THROW</code> meaning the loader + * should throw an <code>OperationInProgressException</code>. * * @throws FileNotFoundException When <code>file</code> does not exist. * @throws IllegalStateException When Ghostscript fails to initialize or load the document. * @throws NullPointerException When <code>file</code> is <code>null</code>. - * @throws OperationInProgressException When an operation is already in progress. + * @throws OperationInProgressException When an operation is already in progress + * and <code>operationMode</code> is <code>OPERATION_THROW</code>. + * @throws IllegalArgumentException When <code>operationMode</code> is not + * <code>OPERATION_WAIT</coded>, <code>OPERATION_RETURN</code>, or <code>OPERATION_THROW</code>. */ public Document(final String filename, final DocLoadProgressCallback loadCallback, final int operationMode) @@ -422,19 +493,37 @@ public class Document implements List<Page> { * Creates and loads a document from a filename. * * @param filename The name of the file to load. - * @throws FileNotFoundException If the given filename does not exist. - * @throws NullPointerException If <code>filename</code> is <code>null</code>. + * @param operationMode How the loader should behave if an operation is already in + * progress. Can be <code>OPERATION_WAIT</code>, meaning the loader should + * wait until a running operation has finished, <code>OPERATION_RETURN</code> meaning + * the loader should immediately return, or <code>OPERATION_THROW</code> meaning the loader + * should throw an <code>OperationInProgressException</code>. + * + * @throws FileNotFoundException When <code>filename</code> does not exist. + * @throws IllegalStateException When Ghostscript fails to initialize or load the document. + * @throws NullPointerException When <code>filename</code> is <code>null</code>. + * @throws OperationInProgressException When an operation is already in progress + * and <code>operationMode</code> is <code>OPERATION_THROW</code>. + * @throws IllegalArgumentException When <code>operationMode</code> is not + * <code>OPERATION_WAIT</coded>, <code>OPERATION_RETURN</code>, or <code>OPERATION_THROW</code>. */ public Document(final String filename, final int operationMode) - throws FileNotFoundException, NullPointerException { + throws FileNotFoundException, IllegalStateException, NullPointerException, + OperationInProgressException { this(filename, null, operationMode); } /** * Loads the high resolution images in a range of images. * + * @param operationMode How the loader should behave if an operation is already in + * progress. Can be <code>OPERATION_WAIT</code>, meaning the loader should + * wait until a running operation has finished, <code>OPERATION_RETURN</code> meaning + * the loader should immediately return, or <code>OPERATION_THROW</code> meaning the loader + * should throw an <code>OperationInProgressException</code>. * @param startPage The first page to load. * @param endPage The end page to load. + * * @throws IndexOutOfBoundsException When <code>firstPage</code> or <code>endPage</code> * are not in the document or <code>endPage</code> is less than <code>firstPage</code>. * @throws IllegalStateException When Ghostscript fails to initialize or load the document. @@ -476,45 +565,68 @@ public class Document implements List<Page> { /** * Loads the high resolution image of a singular page. * + * @param operationMode How the loader should behave if an operation is already in + * progress. Can be <code>OPERATION_WAIT</code>, meaning the loader should + * wait until a running operation has finished, <code>OPERATION_RETURN</code> meaning + * the loader should immediately return, or <code>OPERATION_THROW</code> meaning the loader + * should throw an <code>OperationInProgressException</code>. * @param page The page to load. + * * @throws IndexOutOfBoundsException When <code>page</code> is not in the document. - * @throws IllegalStateException When Ghostscript fails to initialize or load the - * images. + * @throws IllegalStateException When Ghostscript fails to initialize or load the document. + * @throws OperationInProgressException When an operation is already in progress + * and <code>operationMode</code> is <code>OPERATION_THROW</code>. + * @throws IllegalArgumentException When <code>operationMode</code> is not + * <code>OPERATION_WAIT</coded>, <code>OPERATION_RETURN</code>, or <code>OPERATION_THROW</code>. */ public void loadHighRes(int operationMode, int page) - throws IndexOutOfBoundsException, IllegalStateException { - loadHighRes(page, page, operationMode); + throws IndexOutOfBoundsException, IllegalStateException, OperationInProgressException { + loadHighRes(operationMode, page, page); } /** * Loads the high resolution images of a list of pages. * + * @param operationMode How the loader should behave if an operation is already in + * progress. Can be <code>OPERATION_WAIT</code>, meaning the loader should + * wait until a running operation has finished, <code>OPERATION_RETURN</code> meaning + * the loader should immediately return, or <code>OPERATION_THROW</code> meaning the loader + * should throw an <code>OperationInProgressException</code>. * @param pages The pages to load. + * * @throws IndexOutOfBoundsException When any page is not a page in the document. - * @throws IllegalStateException When Ghostscript fails to initialize or load the - * images. + * @throws IllegalStateException When Ghostscript fails to initialize or load the document. + * @throws OperationInProgressException When an operation is already in progress + * and <code>operationMode</code> is <code>OPERATION_THROW</code>. + * @throws IllegalArgumentException When <code>operationMode</code> is not + * <code>OPERATION_WAIT</coded>, <code>OPERATION_RETURN</code>, or <code>OPERATION_THROW</code>. */ - public void loadHighResList(int operationMode, final int... pages) - throws IndexOutOfBoundsException, IllegalStateException { + public void loadHighResList(int operationMode, final int[] pages) + throws IndexOutOfBoundsException, IllegalStateException, OperationInProgressException { if (pages.length > 0) { - final StringBuilder builder = new StringBuilder(); - if (pages[0] < 1 || pages[0] > this.pages.size()) - throw new IndexOutOfBoundsException("page=" + pages[0]); - builder.append(pages[0]); - - for (int i = 1; i < pages.length; i++) { - if (pages[i] < 1 || pages[i] > this.pages.size()) - throw new IndexOutOfBoundsException("page=" + pages[i]); - builder.append(',').append(pages[i]); - } + if (!handleOperationMode(operationMode)) + return; + try { + startOperation(); - final String[] gargs = { "gs", "-dNOPAUSE", "-dSAFER", "-I%rom%Resource%/Init/", "-dBATCH", "-r" + Page.PAGE_HIGH_DPI, - "-sDEVICE=display", "-sPageList=" + builder.toString(), "-dDisplayFormat=" + format, - "-dTextAlphaBits=4", "-dGraphicsAlphaBits=4", - "-f", file.getAbsolutePath() }; + final StringBuilder builder = new StringBuilder(); + if (pages[0] < 1 || pages[0] > this.pages.size()) + throw new IndexOutOfBoundsException("page=" + pages[0]); + builder.append(pages[0]); + + for (int i = 1; i < pages.length; i++) { + if (pages[i] < 1 || pages[i] > this.pages.size()) + throw new IndexOutOfBoundsException("page=" + pages[i]); + builder.append(',').append(pages[i]); + } + + + final String[] gargs = { "gs", "-dNOPAUSE", "-dSAFER", "-I%rom%Resource%/Init/", "-dBATCH", "-r" + Page.PAGE_HIGH_DPI, + "-sDEVICE=display", "-sPageList=" + builder.toString(), "-dDisplayFormat=" + format, + "-dTextAlphaBits=4", "-dGraphicsAlphaBits=4", + "-f", file.getAbsolutePath() }; - synchronized (slock) { LongReference instanceRef = new LongReference(); initDocInstance(instanceRef); @@ -529,6 +641,8 @@ public class Document implements List<Page> { for (final BufferedImage img : documentLoader.images) { this.pages.get(pages[ind] - 1).setHighRes(img); } + } finally { + operationDone(); } } } @@ -538,6 +652,7 @@ public class Document implements List<Page> { * * @param startPage The start page to unload the high resolution image from. * @param endPage The end page to unload the high resolution image from. + * * @throws IndexOutOfBoundsException When <code>startPage</code> and <code>endPage</code> * are outside document or <code>endPage</code> is less than <code>startPage</code>. */ @@ -552,21 +667,22 @@ public class Document implements List<Page> { * Unloads a high resolution image at the given page. * * @param page The page to unload the high resolution image. + * * @throws IndexOutOfBoundsException When page is not a page in the document. */ public void unloadHighRes(int page) throws IndexOutOfBoundsException { unloadHighRes(page, page); } - public void loadZoomed(int operationMode, int startPage, int endPage, double scale) - throws IndexOutOfBoundsException { - checkBounds(startPage, endPage); - } - - public void loadZoomed(int operationMode, int page, double scale) throws IndexOutOfBoundsException { - - } - + /** + * Unloads the zoomed images for a range of pages. + * + * @param startPage The start page to unload. + * @param endPage The end page to unload. + * + * @throws IndexOutOfBoundsException When <code>startPage</code> and <code>endPage</code> + * are outside document or <code>endPage</code> is less than <code>startPage</code>. + */ public void unloadZoomed(int startPage, int endPage) throws IndexOutOfBoundsException { checkBounds(startPage, endPage); for (int i = startPage; i <= endPage; i++) { @@ -574,6 +690,13 @@ public class Document implements List<Page> { } } + /** + * Unloads a zoomed image for a page. + * + * @param page The page to unload. + * + * @throws IndexOutOfBoundsException When <code>page</code> is not in the document. + */ public void unloadZoomed(int page) throws IndexOutOfBoundsException { unloadZoomed(page, page); } @@ -598,50 +721,80 @@ public class Document implements List<Page> { return file.getName(); } - public void zoomArea(final int operationMode, final int page, final double zoom) { + /** + * Zooms the area around page <code>page</code>. The area around <code>page</code> + * is <code>page - 1</code> to <code>page + 1</code>. The method will automatically + * handle if <code>page - 1</code> or <code>page + 1</code> are out of range. However, + * it does not handle if <code>page</code> is not in the document. + * + * @param operationMode How the loader should behave if an operation is already in + * progress. Can be <code>OPERATION_WAIT</code>, meaning the loader should + * wait until a running operation has finished, <code>OPERATION_RETURN</code> meaning + * the loader should immediately return, or <code>OPERATION_THROW</code> meaning the loader + * should throw an <code>OperationInProgressException</code>. + * @param page The page to load around. + * @param zoom The zoom of the pages. + * + * @throws IndexOutOfBoundsException When <code>page</code> is not in the document. + * @throws IllegalStateException When Ghostscript fails to initialize or load the document. + * @throws OperationInProgressException When an operation is already in progress + * and <code>operationMode</code> is <code>OPERATION_THROW</code>. + * @throws IllegalArgumentException When <code>operationMode</code> is not + * <code>OPERATION_WAIT</coded>, <code>OPERATION_RETURN</code>, or <code>OPERATION_THROW</code>. + */ + public void zoomArea(final int operationMode, final int page, final double zoom) + throws IndexOutOfBoundsException { checkBounds(page, page); if (!handleOperationMode(operationMode)) return; - startOperation(); - - int start = page - 1; - start = start < 1 ? page : start; - int end = page + 1; - end = end > pages.size() ? page : end; + try { + startOperation(); + + int start = page - 1; + start = start < 1 ? page : start; + int end = page + 1; + end = end > pages.size() ? page : end; + + final String[] gargs = { + "gs", "-dNOPAUSE", "-dSAFER", "-I%rom%Resource%/Init/", + "-dBATCH", "-r" + (int)(Page.PAGE_HIGH_DPI * zoom), + "-sDEVICE=display", "-dFirstPage=" + start, "-dLastPage=" + end, + "-dDisplayFormat=" + format, + "-dTextAlphaBits=4", "-dGraphicsAlphaBits=4", + "-f", file.getAbsolutePath() }; - final String[] gargs = { - "gs", "-dNOPAUSE", "-dSAFER", "-I%rom%Resource%/Init/", - "-dBATCH", "-r" + (int)(Page.PAGE_HIGH_DPI * zoom), - "-sDEVICE=display", "-dFirstPage=" + start, "-dLastPage=" + end, - "-dDisplayFormat=" + format, - "-dTextAlphaBits=4", "-dGraphicsAlphaBits=4", - "-f", file.getAbsolutePath() }; + LongReference instanceRef = new LongReference(); + initDocInstance(instanceRef); - LongReference instanceRef = new LongReference(); - initDocInstance(instanceRef); + int code = gsapi_init_with_args(instanceRef.value, gargs); + gsapi_exit(instanceRef.value); + gsapi_delete_instance(instanceRef.value); + if (code != GS_ERROR_OK) { + operationDone(); + throw new IllegalStateException("Failed to gsapi_init_with_args code=" + code); + } - int code = gsapi_init_with_args(instanceRef.value, gargs); - gsapi_exit(instanceRef.value); - gsapi_delete_instance(instanceRef.value); - if (code != GS_ERROR_OK) { + int ind = start - 1; + for (final BufferedImage img : documentLoader.images) { + this.pages.get(ind++).setZoomed(img); + } + } finally { operationDone(); - throw new IllegalStateException("Failed to gsapi_init_with_args code=" + code); } - - int ind = start - 1; - for (final BufferedImage img : documentLoader.images) { - this.pages.get(ind++).setZoomed(img); - } - - operationDone(); - } - - public void unZoomPage(final int page) { - checkBounds(page, page); } + /** + * Checks to make sure the pages <code>start</code> through + * <code>end</code> are in the document, and throws an + * <code>IndexOutOfBoundsException</code> if they are not. + * + * @param start The start page. + * @param end The end page. + * @throws IndexOutOfBoundsException When <code>startPage</code> and <code>endPage</code> + * are outside document or <code>endPage</code> is less than <code>startPage</code>. + */ private void checkBounds(int start, int end) throws IndexOutOfBoundsException { if (start < 1 || start > pages.size()) throw new IndexOutOfBoundsException("start=" + start); @@ -651,6 +804,8 @@ public class Document implements List<Page> { throw new IndexOutOfBoundsException("end < start"); } + // Implementations of inherited methods from java.util.List. + @Override public int size() { return pages.size(); |