Version 20, March 2020

[GpsPrune.git] / src / tim / prune / load / ContentCacher.java

diff --git a/src/tim/prune/load/ContentCacher.java b/src/tim/prune/load/ContentCacher.java
new file mode 100644 (file)
index 0000000..623abda
--- /dev/null
+++ b/src/tim/prune/load/ContentCacher.java
@@ -0,0 +1,90 @@
+package tim.prune.load;
+
+import java.util.ArrayList;
+
+/**
+ * General point data cacher
+ */
+public abstract class ContentCacher
+{
+       /** Array to hold lines of file */
+       private String[] _contentArray = null;
+
+
+       /**
+        * @return Contents of the file as array of non-blank Strings
+        */
+       public String[] getContents()
+       {
+               return _contentArray;
+       }
+
+
+       /**
+        * Get the top section of the file for preview
+        * @param inNumRows number of lines to extract
+        * @param inMaxWidth max length of Strings (longer ones will be chopped)
+        * @return String array containing non-blank lines from the file
+        */
+       public String[] getSnippet(int inNumRows, int inMaxWidth)
+       {
+               final int MIN_SNIPPET_SIZE = 3;
+               // Check size is within sensible limits
+               int numToCopy = inNumRows;
+               if (numToCopy > getNumLines()) numToCopy = getNumLines();
+               int size = numToCopy;
+               if (size < MIN_SNIPPET_SIZE) size = MIN_SNIPPET_SIZE;
+               String[] result = new String[size];
+               // Copy Strings across
+               System.arraycopy(_contentArray, 0, result, 0, numToCopy);
+               // Chop Strings to max width if necessary
+               if (inMaxWidth > 10)
+               {
+                       for (int i=0; i<size; i++)
+                       {
+                               if (result[i] == null)
+                                       result[i] = "";
+                               else
+                               {
+                                       if (result[i].length() > inMaxWidth)
+                                               result[i] = result[i].trim();
+                                       if (result[i].length() > inMaxWidth)
+                                               result[i] = result[i].substring(0, inMaxWidth);
+                               }
+                       }
+               }
+               return result;
+       }
+
+       /**
+        * @return the number of non-blank lines in the file
+        */
+       public int getNumLines()
+       {
+               return _contentArray.length;
+       }
+
+
+       /**
+        * Clear the memory
+        */
+       public void clear()
+       {
+               _contentArray = null;
+       }
+
+       /**
+        * Populate the string array
+        * @param inList list of lines
+        */
+       protected void setContents(ArrayList<String> inList)
+       {
+               // Convert into String array for keeps
+               int numLines = inList.size();
+               _contentArray = new String[numLines];
+               for (int i=0; i<numLines; i++)
+               {
+                       _contentArray[i] = inList.get(i);
+               }
+       }
+}