Added options to limit output.

This is useful when handling properties with too much data.

Atlas/PresentationBridge.cpp

@@ -22,7 +22,7 @@ namespace Atlas
 {
 
 PresentationBridge::PresentationBridge(std::stringstream& stream) :
-		mStream(stream)
+		mStream(stream), mMaxItemsPerLevel(0), mIsSkipEntry(false), mStartFilterLevel(1)
 {
     mStream.precision(6);
 }
@@ -46,26 +46,36 @@ void PresentationBridge::streamEnd()
 
 void PresentationBridge::mapMapItem(const std::string& name)
 {
-	mStream << mPadding << name << std::endl;
+	if (checkAndUpdateMaxItemCounter()) {
+        mStream << mPadding << name << std::endl;
+	}
 	addPadding();
 }
 void PresentationBridge::mapListItem(const std::string& name)
 {
+	if (checkAndUpdateMaxItemCounter()) {
+        mStream << mPadding << name << std::endl;
+	}
 	mMapsInList.push(0);
-	mStream << mPadding << name << std::endl;
 	addPadding();
 }
 void PresentationBridge::mapIntItem(const std::string& name, long i)
 {
-	mStream << mPadding << name << ": " << i << std::endl;
+	if (checkAndUpdateMaxItemCounter()) {
+        mStream << mPadding << name << ": " << i << std::endl;
+	}
 }
 void PresentationBridge::mapFloatItem(const std::string& name, double d)
 {
-	mStream << mPadding << name << ": " << std::fixed << d << std::endl;
+	if (checkAndUpdateMaxItemCounter()) {
+        mStream << mPadding << name << ": " << std::fixed << d << std::endl;
+	}
 }
 void PresentationBridge::mapStringItem(const std::string& name, const std::string& s)
 {
-	mStream << mPadding << name << ": " << s << std::endl;
+	if (checkAndUpdateMaxItemCounter()) {
+        mStream << mPadding << name << ": " << s << std::endl;
+	}
 }
 void PresentationBridge::mapEnd()
 {
@@ -74,31 +84,40 @@ void PresentationBridge::mapEnd()
 
 void PresentationBridge::listMapItem()
 {
-	//Check if we've already printed a map for this list, and if so print a separator
 	int items = mMapsInList.top();
-	if (items) {
-		mStream << mPadding << "---" << std::endl;
+	if (checkAndUpdateMaxItemCounter()) {
+        //Check if we've already printed a map for this list, and if so print a separator
+		if (items) {
+			mStream << mPadding << "---" << std::endl;
+		}
 	}
 	mMapsInList.pop();
 	mMapsInList.push(items + 1);
 	addPadding();
 }
+
 void PresentationBridge::listListItem()
 {
 	mMapsInList.push(0);
 	addPadding();
 }
 void PresentationBridge::listIntItem(long i)
 {
-	mStream << mPadding << ": " << i << std::endl;
+	if (checkAndUpdateMaxItemCounter()) {
+        mStream << mPadding << ": " << i << std::endl;
+	}
 }
 void PresentationBridge::listFloatItem(double d)
 {
-	mStream << mPadding << ": " << d << std::endl;
+	if (checkAndUpdateMaxItemCounter()) {
+        mStream << mPadding << ": " << d << std::endl;
+	}
 }
 void PresentationBridge::listStringItem(const std::string& s)
 {
-	mStream << mPadding << ": " << s << std::endl;
+	if (checkAndUpdateMaxItemCounter()) {
+        mStream << mPadding << ": " << s << std::endl;
+	}
 }
 void PresentationBridge::listEnd()
 {
@@ -107,12 +126,55 @@ void PresentationBridge::listEnd()
 }
 void PresentationBridge::addPadding()
 {
+	mEntriesPerLevelCounter.push_back(0);
 	mPadding += "  ";
 }
 
 void PresentationBridge::removePadding()
 {
+    size_t itemsThisLevel = mEntriesPerLevelCounter.back();
+    bool wasSkipping = mIsSkipEntry;
+	mEntriesPerLevelCounter.pop_back();
+	if (mMaxItemsPerLevel) {
+        size_t level = 0;
+		for (size_t entry : mEntriesPerLevelCounter) {
+			mIsSkipEntry = entry >= mMaxItemsPerLevel && level >= mStartFilterLevel;
+            level++;
+		}
+	}
+
+    if (wasSkipping != mIsSkipEntry) {
+        mStream << mPadding << "... (" << (itemsThisLevel - mMaxItemsPerLevel) << " more items) ..." << std::endl;
+    }
+
 	mPadding.erase(mPadding.end() - 2, mPadding.end());
 }
 
+void PresentationBridge::setMaxItemsPerLevel(size_t maxItems)
+{
+	mMaxItemsPerLevel = maxItems;
+}
+
+void PresentationBridge::setStartFilteringLevel(size_t startFilteringLevel)
+{
+    mStartFilterLevel = startFilteringLevel;
+}
+
+bool PresentationBridge::checkAndUpdateMaxItemCounter()
+{
+
+	if (mMaxItemsPerLevel && !mEntriesPerLevelCounter.empty() && mEntriesPerLevelCounter.size() > mStartFilterLevel) {
+		size_t& itemsInLevel = mEntriesPerLevelCounter.back();
+		itemsInLevel++;
+		if (itemsInLevel >= mMaxItemsPerLevel) {
+			mIsSkipEntry = true;
+		}
+        if (mIsSkipEntry) {
+            return false;
+        }
+	}
+	return true;
+}
+
+
 }

Atlas/PresentationBridge.h

@@ -22,6 +22,7 @@
 #include <sstream>
 #include <string>
 #include <stack>
+#include <deque>
 #include "Bridge.h"
 
 namespace Atlas
@@ -55,12 +56,34 @@ class PresentationBridge: public Atlas::Bridge
 	virtual void listStringItem(const std::string&);
 	virtual void listEnd();
 
+	/**
+	 * Sets the max number of items to print per level.
+	 *
+	 * This is useful to prevent too much output.
+	 *
+	 * @param maxItems The max number of items. 0 disables this feature (which is the default).
+	 */
+	void setMaxItemsPerLevel(size_t maxItems);
+
+	/**
+	 * Sets the level at which filtering, if setMaxItemsPerLevel() has been called, should occur.
+	 * Default is 1 (i.e. print everything for the top level).
+	 * @param startFilteringLevel At which level filtering should start.
+	 */
+	void setStartFilteringLevel(size_t startFilteringLevel);
+
 private:
 
 	void addPadding();
 
 	void removePadding();
 
+	/**
+	 * Checks if the current item should be printed or not, depending on if mMaxItemsPerLevel is set.
+	 * @return True if the current item should be printed.
+	 */
+	bool checkAndUpdateMaxItemCounter();
+
 	std::string mPadding;
 
 	std::stringstream& mStream;
@@ -71,6 +94,27 @@ class PresentationBridge: public Atlas::Bridge
 	 * This is used to determine if we should print a separator to make it easier to see where a new map starts.
 	 */
 	std::stack<int> mMapsInList;
+
+	/**
+	 * If set to > 0 denotes the max number of items to print (per level).
+	 */
+	size_t mMaxItemsPerLevel;
+
+	/**
+	 * Set to true when entries should be skipped because the max number of items for a level has been reached.
+	 */
+	bool mIsSkipEntry;
+
+	/**
+	 * Denotes the level at which filtering through the mMaxItemsPerLevel field should occur.
+	 * Set by default to 1 (i.e. always print all entries on the first level).
+	 */
+	size_t mStartFilterLevel;
+
+	/**
+	 * Keeps track of the number of entries in each level. Used when mMaxItemsPerLevel is > 0.
+	 */
+	std::deque<size_t> mEntriesPerLevelCounter;
 };
 
 }