Cleanup display package and add docs.

src/main/java/com/onarandombox/MultiverseCore/commandTools/display/ColourAlternator.java

@@ -9,30 +9,49 @@ package com.onarandombox.MultiverseCore.commandTools.display;
 
 import org.bukkit.ChatColor;
 
+/**
+ * Some helper class to alternate between 2 colours.
+ */
 public class ColourAlternator {
 
     private boolean switcher;
-    private final ChatColor colorThis;
+    private final ChatColor thisColour;
-    private final ChatColor colorThat;
+    private final ChatColor thatColour;
 
     public ColourAlternator(ChatColor colorThis, ChatColor colorThat) {
-        this.colorThis = colorThis;
+        this.thisColour = colorThis;
-        this.colorThat = colorThat;
+        this.thatColour = colorThat;
     }
 
+    /**
+     * Gives you {@link ColourAlternator#thisColour} or {@link ColourAlternator#thatColour}.
+     *
+     * @return Opposite of the previous colour.
+     */
     public ChatColor get() {
-        return (switcher ^= true) ? colorThis : colorThat;
+        return (switcher ^= true) ? thisColour : thatColour;
     }
 
+    /**
+     * Set back to be {@link ColourAlternator#thisColour} when {@link ColourAlternator#get()} is called.
+     */
     public void reset() {
         switcher = false;
     }
 
-    public ChatColor getColorThis() {
+    /**
-        return colorThis;
+     *
+     * @return {@link ColourAlternator#thisColour}.
+     */
+    public ChatColor getThis() {
+        return thisColour;
     }
 
-    public ChatColor getColorThat() {
+    /**
-        return colorThat;
+     *
+     * @return {@link ColourAlternator#thatColour}.
+     */
+    public ChatColor getThat() {
+        return thatColour;
     }
 }

src/main/java/com/onarandombox/MultiverseCore/commandTools/display/ContentCreator.java

@@ -1,5 +1,10 @@
 package com.onarandombox.MultiverseCore.commandTools.display;
 
+/**
+ * Generate content for displaying with {@link ContentDisplay}.
+ *
+ * @param <T> Type of content to create.
+ */
 @FunctionalInterface
 public interface ContentCreator<T> {
     T generateContent();

src/main/java/com/onarandombox/MultiverseCore/commandTools/display/ContentDisplay.java

@@ -5,6 +5,11 @@ import org.bukkit.plugin.Plugin;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+/**
+ * Displays various types of content to sender.
+ *
+ * @param <T> Type of content to display.
+ */
 public abstract class ContentDisplay<T> {
 
     protected final Plugin plugin;
@@ -28,15 +33,26 @@ public abstract class ContentDisplay<T> {
         this.colours = colours;
     }
 
+    /**
+     * Display the content to the {@link ContentDisplay#sender}.
+     */
     public void showContent() {
-        getShowPageRunnable().runTask(this.plugin);
+        getShowRunnable().runTask(this.plugin);
     }
 
+    /**
+     * Display the content to the {@link ContentDisplay#sender} with a asynchronous task.
+     */
     public void showContentAsync() {
-        getShowPageRunnable().runTaskAsynchronously(this.plugin);
+        getShowRunnable().runTaskAsynchronously(this.plugin);
     }
 
-    public abstract ShowRunnable<T> getShowPageRunnable();
+    /**
+     * Runnable used to format and display contents to
+     *
+     * @return {@link ShowRunnable}
+     */
+    public abstract ShowRunnable<? extends ContentDisplay<T>, T> getShowRunnable();
 
     public CommandSender getSender() {
         return sender;

src/main/java/com/onarandombox/MultiverseCore/commandTools/display/ContentFilter.java

@@ -8,6 +8,9 @@ import org.jetbrains.annotations.Nullable;
 import java.util.regex.Pattern;
 import java.util.regex.PatternSyntaxException;
 
+/**
+ * Filter content and text based on regex.
+ */
 public class ContentFilter {
     private final String filterString;
     private Pattern filterPattern;
@@ -32,6 +35,9 @@ public class ContentFilter {
         parseFilter();
     }
 
+    /**
+     * Compile regex pattern based on {@link ContentFilter#filterString}.
+     */
     private void parseFilter() {
         if (filterString == null) {
             return;
@@ -41,10 +47,12 @@ public class ContentFilter {
             parseCustomFilter();
             return;
         }
-        String cleanedFilter = REGEX_SPECIAL_CHARS.matcher(filterString.toLowerCase()).replaceAll("\\\\$0");
+        parseContainsFilter();
-        this.filterPattern = Pattern.compile("(?i).*" + cleanedFilter + ".*");
     }
 
+    /**
+     * When prefixed with 'r=', use {@link ContentFilter#filterString} as the full regex pattern.
+     */
     private void parseCustomFilter() {
         try {
             this.filterPattern = Pattern.compile(filterString.substring(2));
@@ -55,14 +63,25 @@ public class ContentFilter {
         }
     }
 
-    public boolean checkMatch(@Nullable String text) {
+    /**
-        if (text == null) {
+     * Set pattern that matches any text that contains {@link ContentFilter#filterString}.
-            return false;
+     */
+    private void parseContainsFilter() {
+        String cleanedFilter = REGEX_SPECIAL_CHARS.matcher(filterString.toLowerCase()).replaceAll("\\\\$0");
+        this.filterPattern = Pattern.compile("(?i).*" + cleanedFilter + ".*");
     }
+
+    /**
+     * Do regex matching.
+     *
+     * @param text String to check regex on.
+     * @return True of matches regex pattern, false otherwise.
+     */
+    public boolean checkMatch(@Nullable String text) {
         if (!hasFilter()) {
             return true;
         }
-        if (!hasValidPattern()) {
+        if (text == null || !hasValidPattern()) {
             return false;
         }
         text = ChatColor.stripColor(text);
@@ -93,12 +112,16 @@ public class ContentFilter {
         return exactMatch;
     }
 
+    /**
+     * Nicely format the filter string to be used for showing the sender.
+     *
+     * @return formatted filter string.
+     */
     @NotNull
     public String getFormattedString() {
         return String.format("%sFilter: '%s'%s", ChatColor.ITALIC, filterString, ChatColor.RESET);
     }
 
-
     @Override
     public String toString() {
         return "ContentFilter{" +

src/main/java/com/onarandombox/MultiverseCore/commandTools/display/ShowRunnable.java

@@ -2,30 +2,70 @@ package com.onarandombox.MultiverseCore.commandTools.display;
 
 import org.bukkit.scheduler.BukkitRunnable;
 
-public abstract class ShowRunnable<T> extends BukkitRunnable {
+/**
+ *
+ * @param <D> {@link ContentDisplay} type that is targted to.
+ * @param <T> Type of content its displaying.
+ */
+public abstract class ShowRunnable<D extends ContentDisplay<T>, T> extends BukkitRunnable {
 
-    protected final T contents;
+    protected final D display;
+    protected T contents;
 
-    protected ShowRunnable(ContentDisplay<T> display) {
+    protected ShowRunnable(D display) {
-        this.contents = display.getCreator().generateContent();
+        this.display = display;
     }
 
+    /**
+     * Run the showing of {@link ContentDisplay}.
+     */
     @Override
     public void run() {
+        this.contents = this.display.getCreator().generateContent();
         calculateContent();
+        if (!validateContent()) {
+            return;
+        }
+        if (!hasContentToShow()) {
+            this.display.getSender().sendMessage("No matching content to display.");
+            return;
+        }
         display();
     }
 
+    /**
+     * Show header and contents to sender.
+     */
     public void display() {
         showHeader();
         showContent();
     }
 
+    /**
+     * Generate the content to show based on filter, pages or other factors depending on implementation.
+     */
     public abstract void calculateContent();
 
+    /**
+     * Check if there is anything to show after {@link ShowRunnable#calculateContent()}.
+     *
+     * @return True if content is present, false otherwise.
+     */
+    public abstract boolean hasContentToShow();
+
+    /**
+     *
+     * @return True if valid, false otherwise.
+     */
     public abstract boolean validateContent();
 
+    /**
+     * Displays header to the sender.
+     */
     public abstract void showHeader();
 
+    /**
+     * Displays content to the sender.
+     */
     public abstract void showContent();
 }

src/main/java/com/onarandombox/MultiverseCore/commandTools/display/kvpair/KeyValueDisplay.java

@@ -4,7 +4,6 @@ import com.onarandombox.MultiverseCore.commandTools.display.ColourAlternator;
 import com.onarandombox.MultiverseCore.commandTools.display.ContentCreator;
 import com.onarandombox.MultiverseCore.commandTools.display.ContentDisplay;
 import com.onarandombox.MultiverseCore.commandTools.display.ContentFilter;
-import com.onarandombox.MultiverseCore.commandTools.display.ShowRunnable;
 import org.bukkit.command.CommandSender;
 import org.bukkit.plugin.Plugin;
 import org.jetbrains.annotations.NotNull;
@@ -12,6 +11,9 @@ import org.jetbrains.annotations.Nullable;
 
 import java.util.Map;
 
+/**
+ * Used to display config/property values pair, each separated with a comma.
+ */
 public class KeyValueDisplay extends ContentDisplay<Map<String, Object>> {
 
     private final String operator;
@@ -28,8 +30,11 @@ public class KeyValueDisplay extends ContentDisplay<Map<String, Object>> {
         this.operator = operator;
     }
 
+    /**
+     * {@inheritDoc}
+     */
     @Override
-    public ShowRunnable<Map<String, Object>> getShowPageRunnable() {
+    public ShowKeyValue getShowRunnable() {
         return new ShowKeyValue(this);
     }
 

src/main/java/com/onarandombox/MultiverseCore/commandTools/display/kvpair/ShowKeyValue.java

@@ -1,20 +1,17 @@
 package com.onarandombox.MultiverseCore.commandTools.display.kvpair;
 
-import com.dumptruckman.minecraft.util.Logging;
 import com.onarandombox.MultiverseCore.commandTools.display.ContentFilter;
 import com.onarandombox.MultiverseCore.commandTools.display.ShowRunnable;
 import org.bukkit.ChatColor;
 
 import java.util.Map;
 
-public class ShowKeyValue extends ShowRunnable<Map<String, Object>> {
+public class ShowKeyValue extends ShowRunnable<KeyValueDisplay, Map<String, Object>> {
 
     private final StringBuilder contentBuilder;
-    private final KeyValueDisplay display;
 
     public ShowKeyValue(KeyValueDisplay display) {
         super(display);
-        this.display = display;
         this.contentBuilder = new StringBuilder();
     }
 
@@ -32,19 +29,24 @@ public class ShowKeyValue extends ShowRunnable<Map<String, Object>> {
             else {
                 contentBuilder.append(", ");
             }
-            contentBuilder.append(this.display.getColours().getColorThis())
+            contentBuilder.append(this.display.getColours().getThis())
                     .append(entry.getKey())
                     .append(ChatColor.WHITE)
                     .append(this.display.getOperator())
-                    .append(this.display.getColours().getColorThat())
+                    .append(this.display.getColours().getThat())
                     .append(entry.getValue())
                     .append(ChatColor.WHITE);
         }
     }
 
+    @Override
+    public boolean hasContentToShow() {
+        return contentBuilder.length() == 0;
+    }
+
     @Override
     public boolean validateContent() {
-        return false;
+        return true;
     }
 
     @Override
@@ -52,7 +54,6 @@ public class ShowKeyValue extends ShowRunnable<Map<String, Object>> {
         if (this.display.getHeader() == null) {
             return;
         }
-
         this.display.getSender().sendMessage(this.display.getHeader());
     }
 

src/main/java/com/onarandombox/MultiverseCore/commandTools/display/page/PageDisplay.java

@@ -7,12 +7,10 @@
 
 package com.onarandombox.MultiverseCore.commandTools.display.page;
 
-import com.onarandombox.MultiverseCore.commandTools.PageFilter;
 import com.onarandombox.MultiverseCore.commandTools.display.ColourAlternator;
 import com.onarandombox.MultiverseCore.commandTools.display.ContentCreator;
 import com.onarandombox.MultiverseCore.commandTools.display.ContentDisplay;
 import com.onarandombox.MultiverseCore.commandTools.display.ContentFilter;
-import com.onarandombox.MultiverseCore.commandTools.display.ShowRunnable;
 import org.bukkit.command.CommandSender;
 import org.bukkit.command.ConsoleCommandSender;
 import org.bukkit.plugin.Plugin;
@@ -21,6 +19,9 @@ import org.jetbrains.annotations.Nullable;
 
 import java.util.List;
 
+/**
+ * Used to display list of multiple lines with paging and filter.
+ */
 public class PageDisplay extends ContentDisplay<List<String>> {
 
     private final int pageToShow;
@@ -45,8 +46,11 @@ public class PageDisplay extends ContentDisplay<List<String>> {
         this.contentLinesPerPage = contentLinesPerPage;
     }
 
+    /**
+     * {@inheritDoc}
+     */
     @Override
-    public ShowRunnable<List<String>> getShowPageRunnable() {
+    public ShowPage getShowRunnable() {
         return (this.sender instanceof ConsoleCommandSender)
                 ? new ShowAllPage(this)
                 : new ShowSelectedPage(this);

src/main/java/com/onarandombox/MultiverseCore/commandTools/display/page/ShowAllPage.java

@@ -1,8 +1,6 @@
 package com.onarandombox.MultiverseCore.commandTools.display.page;
 
 import com.onarandombox.MultiverseCore.commandTools.display.ContentFilter;
-import com.onarandombox.MultiverseCore.commandTools.display.page.PageDisplay;
-import com.onarandombox.MultiverseCore.commandTools.display.page.ShowPage;
 
 public class ShowAllPage extends ShowPage {
 
@@ -10,6 +8,9 @@ public class ShowAllPage extends ShowPage {
         super(display);
     }
 
+    /**
+     * {@inheritDoc}
+     */
     @Override
     public void calculateContent() {
         int index = -1;
@@ -22,11 +23,17 @@ public class ShowAllPage extends ShowPage {
         }
     }
 
+    /**
+     * {@inheritDoc}
+     */
     @Override
     public boolean validateContent() {
         return true;
     }
 
+    /**
+     * {@inheritDoc}
+     */
     @Override
     public void showHeader() {
         if (this.display.getHeader() == null) {

src/main/java/com/onarandombox/MultiverseCore/commandTools/display/page/ShowPage.java

@@ -6,14 +6,12 @@ import com.onarandombox.MultiverseCore.commandTools.display.ShowRunnable;
 import java.util.ArrayList;
 import java.util.List;
 
-public abstract class ShowPage extends ShowRunnable<List<String>> {
+public abstract class ShowPage extends ShowRunnable<PageDisplay, List<String>> {
 
-    protected PageDisplay display;
     protected final List<Integer> contentToShowIndex;
 
     public ShowPage(PageDisplay display) {
         super(display);
-        this.display = display;
         this.contentToShowIndex = new ArrayList<>();
 
         if (this.display.getColours() != null) {
@@ -21,19 +19,17 @@ public abstract class ShowPage extends ShowRunnable<List<String>> {
         }
     }
 
+    /**
+     * {@inheritDoc}
+     */
     @Override
-    public void run() {
+    public boolean hasContentToShow() {
-        calculateContent();
+        return !contentToShowIndex.isEmpty();
-        if (!validateContent()) {
-            return;
-        }
-        if (contentToShowIndex.isEmpty()) {
-            this.display.getSender().sendMessage("No matching content to display.");
-            return;
-        }
-        display();
     }
 
+    /**
+     * {@inheritDoc}
+     */
     @Override
     public void showContent() {
         ColourAlternator colours = this.display.getColours();

src/main/java/com/onarandombox/MultiverseCore/commandTools/display/page/ShowSelectedPage.java

@@ -12,12 +12,18 @@ public class ShowSelectedPage extends ShowPage {
         super(display);
     }
 
+    /**
+     * {@inheritDoc}
+     */
     @Override
     public void display() {
         super.display();
         doEndPadding();
     }
 
+    /**
+     * {@inheritDoc}
+     */
     @Override
     public void calculateContent() {
         int lineCount = 0;
@@ -41,6 +47,9 @@ public class ShowSelectedPage extends ShowPage {
         }
     }
 
+    /**
+     * {@inheritDoc}
+     */
     @Override
     public boolean validateContent() {
         return !pageOutOfRange();
@@ -56,25 +65,32 @@ public class ShowSelectedPage extends ShowPage {
         return false;
     }
 
+    /**
+     * {@inheritDoc}
+     */
     @Override
     public void showHeader() {
-        String theHeader;
+        String header = getHeader();
-        if (this.display.getHeader() == null) {
-            theHeader = this.contents.get(contentToShowIndex.remove(0));
-            this.display.reduceContentLinesPerPage(1);
-        }
-        else {
-            theHeader = this.display.getHeader();
-        }
 
-        if (theHeader.contains(PageDisplay.PAGE_PLACEHOLDER)) {
+        // Paging inline with header
-            this.display.getSender().sendMessage(theHeader.replace(PageDisplay.PAGE_PLACEHOLDER, parsePaging()));
+        if (header.contains(PageDisplay.PAGE_PLACEHOLDER)) {
+            this.display.getSender().sendMessage(header.replace(PageDisplay.PAGE_PLACEHOLDER, parsePaging()));
             return;
         }
-        this.display.getSender().sendMessage(theHeader);
+
+        this.display.getSender().sendMessage(header);
         this.display.getSender().sendMessage(parsePaging());
     }
 
+    private String getHeader() {
+        if (this.display.getHeader() != null) {
+            return this.display.getHeader();
+        }
+        // Let first content line be the header.
+        this.display.reduceContentLinesPerPage(1);
+        return this.contents.get(contentToShowIndex.remove(0));
+    }
+
     private String parsePaging() {
         ContentFilter filter = this.display.getFilter();
         return (filter.hasFilter())

src/main/java/com/onarandombox/MultiverseCore/commands/SubModulesCommand.java

@@ -72,8 +72,8 @@ public class SubModulesCommand {
                                         @NotNull ColourAlternator colours,
                                         @NotNull String downloadLink) {
 
-        sender.sendMessage(colours.getColorThis() + pluginName + ChatColor.WHITE +
+        sender.sendMessage(colours.getThis() + pluginName + ChatColor.WHITE +
                 " is not installed on this server. You can learn more and download it at:");
-        sender.sendMessage(colours.getColorThat() + downloadLink);
+        sender.sendMessage(colours.getThat() + downloadLink);
     }
 }