Reimplement markdown table builder.

Author: Darkhax

Common/src/main/java/net/darkhax/bookshelf/api/lib/TableBuilder.java

@@ -0,0 +1,117 @@
+package net.darkhax.bookshelf.api.lib;
+
+import org.apache.commons.lang3.StringUtils;
+
+import java.util.LinkedList;
+import java.util.List;
+import java.util.function.Function;
+
+public class TableBuilder<T> {
+
+    private static final String NEW_LINE = System.lineSeparator();
+
+    private static final String DIVIDER_COLUMN = "|";
+
+    private static final String DIVIDER_ROW = "-";
+
+    private final List<TableColumn<T>> columns = new LinkedList<>();
+    private int entryCount = 0;
+
+    public TableBuilder<T> addColumn(String name, Function<T, Object> function) {
+
+        this.columns.add(new TableColumn<>(name, function));
+        return this;
+    }
+
+    public void addAll(Iterable<T> entries) {
+
+        entries.forEach(this::addEntry);
+    }
+
+    public void addEntry(T entry) {
+
+        columns.forEach(column -> column.processValue(entry));
+        entryCount++;
+    }
+
+    @Override
+    public String toString() {
+
+        final StringBuilder builder = new StringBuilder();
+
+        // Column Names
+        for (TableColumn<T> column : this.columns) {
+
+            builder.append(DIVIDER_COLUMN).append(" ").append(StringUtils.rightPad(column.getTitle(), column.getMaxLength())).append(" ");
+        }
+
+        builder.append(DIVIDER_COLUMN).append(NEW_LINE);
+
+        // Entry Separator
+        for (TableColumn<T> column : this.columns) {
+
+            builder.append(DIVIDER_COLUMN).append(DIVIDER_ROW.repeat(column.getMaxLength() + 2));
+        }
+
+        builder.append(DIVIDER_COLUMN).append(NEW_LINE);
+
+        for (int entryIndex = 0; entryIndex < entryCount; entryIndex++) {
+
+            for (TableColumn<T> column : this.columns) {
+
+                builder.append(DIVIDER_COLUMN).append(" ").append(StringUtils.rightPad(column.getValue(entryIndex), column.getMaxLength())).append(" ");
+            }
+
+            builder.append(DIVIDER_COLUMN);
+
+            if (entryIndex != entryCount - 1) {
+
+                builder.append(NEW_LINE);
+            }
+        }
+
+        return builder.toString();
+    }
+
+    public static class TableColumn<T> {
+
+        private final String title;
+        private final Function<T, Object> valueResolver;
+        private final List<String> heldValues;
+        private int maxLength;
+
+        public TableColumn(String title, Function<T, Object> valueResolver) {
+
+            this.title = title;
+            this.valueResolver = valueResolver;
+            this.heldValues = new LinkedList<>();
+            this.maxLength = this.title.length();
+        }
+
+        public String getTitle() {
+
+            return this.title;
+        }
+
+        public String getValue(int index) {
+
+            return this.heldValues.get(index);
+        }
+
+        public void processValue(T value) {
+
+            final String valueText = String.valueOf(this.valueResolver.apply(value));
+            heldValues.add(valueText);
+
+            if (valueText.length() > maxLength) {
+
+                this.maxLength = valueText.length();
+            }
+        }
+
+        public int getMaxLength() {
+
+            return this.maxLength;
+        }
+    }
+}