--- old/src/com/sun/org/apache/regexp/internal/REProgram.java	2020-08-13 14:42:46.077387281 +0100
+++ /dev/null	2020-07-29 22:46:31.398000849 +0100
@@ -1,158 +0,0 @@
-/*
- * reserved comment block
- * DO NOT REMOVE OR ALTER!
- */
-/*
- * Copyright 1999-2004 The Apache Software Foundation.
- *
- * Licensed 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 com.sun.org.apache.regexp.internal;
-
-import java.io.Serializable;
-
-/**
- * A class that holds compiled regular expressions.  This is exposed mainly
- * for use by the recompile utility (which helps you produce precompiled
- * REProgram objects). You should not otherwise need to work directly with
- * this class.
-*
- * @see RE
- * @see RECompiler
- *
- * @author <a href="mailto:jonl@muppetlabs.com">Jonathan Locke</a>
- */
-public class REProgram implements Serializable
-{
-    static final int OPT_HASBACKREFS = 1;
-
-    char[] instruction;         // The compiled regular expression 'program'
-    int lenInstruction;         // The amount of the instruction buffer in use
-    char[] prefix;              // Prefix string optimization
-    int flags;                  // Optimization flags (REProgram.OPT_*)
-    int maxParens = -1;
-
-    /**
-     * Constructs a program object from a character array
-     * @param instruction Character array with RE opcode instructions in it
-     */
-    public REProgram(char[] instruction)
-    {
-        this(instruction, instruction.length);
-    }
-
-    /**
-     * Constructs a program object from a character array
-     * @param parens Count of parens in the program
-     * @param instruction Character array with RE opcode instructions in it
-     */
-    public REProgram(int parens, char[] instruction)
-    {
-        this(instruction, instruction.length);
-        this.maxParens = parens;
-    }
-
-    /**
-     * Constructs a program object from a character array
-     * @param instruction Character array with RE opcode instructions in it
-     * @param lenInstruction Amount of instruction array in use
-     */
-    public REProgram(char[] instruction, int lenInstruction)
-    {
-        setInstructions(instruction, lenInstruction);
-    }
-
-    /**
-     * Returns a copy of the current regular expression program in a character
-     * array that is exactly the right length to hold the program.  If there is
-     * no program compiled yet, getInstructions() will return null.
-     * @return A copy of the current compiled RE program
-     */
-    public char[] getInstructions()
-    {
-        // Ensure program has been compiled!
-        if (lenInstruction != 0)
-        {
-            // Return copy of program
-            char[] ret = new char[lenInstruction];
-            System.arraycopy(instruction, 0, ret, 0, lenInstruction);
-            return ret;
-        }
-        return null;
-    }
-
-    /**
-     * Sets a new regular expression program to run.  It is this method which
-     * performs any special compile-time search optimizations.  Currently only
-     * two optimizations are in place - one which checks for backreferences
-     * (so that they can be lazily allocated) and another which attempts to
-     * find an prefix anchor string so that substantial amounts of input can
-     * potentially be skipped without running the actual program.
-     * @param instruction Program instruction buffer
-     * @param lenInstruction Length of instruction buffer in use
-     */
-    public void setInstructions(char[] instruction, int lenInstruction)
-    {
-        // Save reference to instruction array
-        this.instruction = instruction;
-        this.lenInstruction = lenInstruction;
-
-        // Initialize other program-related variables
-        flags = 0;
-        prefix = null;
-
-        // Try various compile-time optimizations if there's a program
-        if (instruction != null && lenInstruction != 0)
-        {
-            // If the first node is a branch
-            if (lenInstruction >= RE.nodeSize && instruction[0 + RE.offsetOpcode] == RE.OP_BRANCH)
-            {
-                // to the end node
-                int next = instruction[0 + RE.offsetNext];
-                if (instruction[next + RE.offsetOpcode] == RE.OP_END)
-                {
-                    // and the branch starts with an atom
-                    if (lenInstruction >= (RE.nodeSize * 2) && instruction[RE.nodeSize + RE.offsetOpcode] == RE.OP_ATOM)
-                    {
-                        // then get that atom as an prefix because there's no other choice
-                        int lenAtom = instruction[RE.nodeSize + RE.offsetOpdata];
-                        prefix = new char[lenAtom];
-                        System.arraycopy(instruction, RE.nodeSize * 2, prefix, 0, lenAtom);
-                    }
-                }
-            }
-
-            BackrefScanLoop:
-
-            // Check for backreferences
-            for (int i = 0; i < lenInstruction; i += RE.nodeSize)
-            {
-                switch (instruction[i + RE.offsetOpcode])
-                {
-                    case RE.OP_ANYOF:
-                        i += (instruction[i + RE.offsetOpdata] * 2);
-                        break;
-
-                    case RE.OP_ATOM:
-                        i += instruction[i + RE.offsetOpdata];
-                        break;
-
-                    case RE.OP_BACKREF:
-                        flags |= OPT_HASBACKREFS;
-                        break BackrefScanLoop;
-                }
-            }
-        }
-    }
-}