Add MirrorDB

This adds a simple map that uses the unicode bidirectional database to
say whether or not a given character has a mirrored counterpart (e.g, (
and ), < and >, as well as « and »)

1 files changed, 52 insertions, 0 deletions

diff --git a/base/src/main/java/bjc/utils/ioutils/MirrorDB.java b/base/src/main/java/bjc/utils/ioutils/MirrorDB.java
new file mode 100644
index 0000000..230f2f0
--- /dev/null
+++ b/base/src/main/java/bjc/utils/ioutils/MirrorDB.java
@@ -0,0 +1,52 @@
+package bjc.utils.ioutils;
+
+import java.io.InputStream;
+import java.io.IOException;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Scanner;
+
+public class MirrorDB {
+	private Map<String, String> mirrored;
+
+	public MirrorDB() {
+		mirrored = new HashMap<>();
+
+		final InputStream stream = getClass().getResourceAsStream("/BidiMirrorDB.txt");
+
+		try (Scanner scn = new Scanner(stream)) {
+			String ln = "";
+
+			while (scn.hasNextLine()) {
+				ln = scn.nextLine();
+
+				if (ln.equals("")) {
+					continue;
+				}
+				if (ln.startsWith("#")) {
+					continue;
+				}
+
+				final int cp1 = Integer.parseInt(ln.substring(0, 4), 16);
+				final int cp2 = Integer.parseInt(ln.substring(6, 10), 16);
+
+				final char[] cpa1 = Character.toChars(cp1);
+				final char[] cpa2 = Character.toChars(cp2);
+
+				final String cps1 = new String(cpa1);
+				final String cps2 = new String(cpa2);
+
+				mirrored.put(cps1, cps2);
+			}
+		}
+	}
+
+	public boolean canMirror(String mir) {
+		return mirrored.containsKey(mir);
+	}
+
+	public String mirror(String mir) {
+		return mirrored.get(mir);
+	}
+}