1 files changed, 83 insertions, 0 deletions
diff --git a/src/main/java/org/apache/commons/lang3/text/translate/OctalUnescaper.java b/src/main/java/org/apache/commons/lang3/text/translate/OctalUnescaper.java
new file mode 100644
index 000000000..7f37e449f
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+++ b/src/main/java/org/apache/commons/lang3/text/translate/OctalUnescaper.java
@@ -0,0 +1,83 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.lang3.text.translate;
+
+import java.io.IOException;
+import java.io.Writer;
+
+/**
+ * Translate escaped octal Strings back to their octal values.
+ *
+ * For example, "\45" should go back to being the specific value (a %).
+ *
+ * Note that this currently only supports the viable range of octal for Java; namely
+ * 1 to 377. This is because parsing Java is the main use case.
+ *
+ * @since 3.0
+ * @deprecated As of 3.6, use Apache Commons Text
+ * <a href="https://commons.apache.org/proper/commons-text/javadocs/api-release/org/apache/commons/text/translate/OctalUnescaper.html">
+ * OctalUnescaper</a> instead
+ */
+@Deprecated
+public class OctalUnescaper extends CharSequenceTranslator {
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public int translate(final CharSequence input, final int index, final Writer out) throws IOException {
+        final int remaining = input.length() - index - 1; // how many characters left, ignoring the first \
+        final StringBuilder builder = new StringBuilder();
+        if (input.charAt(index) == '\\' && remaining > 0 && isOctalDigit(input.charAt(index + 1)) ) {
+            final int next = index + 1;
+            final int next2 = index + 2;
+            final int next3 = index + 3;
+
+            // we know this is good as we checked it in the if block above
+            builder.append(input.charAt(next));
+
+            if (remaining > 1 && isOctalDigit(input.charAt(next2))) {
+                builder.append(input.charAt(next2));
+                if (remaining > 2 && isZeroToThree(input.charAt(next)) && isOctalDigit(input.charAt(next3))) {
+                    builder.append(input.charAt(next3));
+                }
+            }
+
+            out.write( Integer.parseInt(builder.toString(), 8) );
+            return 1 + builder.length();
+        }
+        return 0;
+    }
+
+    /**
+     * Checks if the given char is an octal digit. Octal digits are the character representations of the digits 0 to 7.
+     * @param ch the char to check
+     * @return true if the given char is the character representation of one of the digits from 0 to 7
+     */
+    private boolean isOctalDigit(final char ch) {
+        return ch >= '0' && ch <= '7';
+    }
+
+    /**
+     * Checks if the given char is the character representation of one of the digit from 0 to 3.
+     * @param ch the char to check
+     * @return true if the given char is the character representation of one of the digits from 0 to 3
+     */
+    private boolean isZeroToThree(final char ch) {
+        return ch >= '0' && ch <= '3';
+    }
+}