java: prefer ArrayList to Vector

Vector is synchronized, which is completely useless in our case (and
not even relevant when concurrency matters).  No seasoned Java
programmer would use it.
Reported by Uxio Prego.

* data/skeletons/lalr1.java: Replace Vector with ArrayList.
Unfortunately its API is not as rich, and lacks lastElement and
setSize.

data/skeletons/lalr1.java

@@ -102,7 +102,7 @@ b4_output_begin([b4_parser_file_name])[
 ]b4_user_pre_prologue[
 ]b4_user_post_prologue[
 import java.text.MessageFormat;
-import java.util.Vector;
+import java.util.ArrayList;
 ]b4_percent_code_get([[imports]])[
 /**
  * A Bison parser, automatically generated from <tt>]m4_bpatsubst(b4_file_name, [^"\(.*\)"$], [\1])[</tt>.
@@ -268,7 +268,7 @@ import java.util.Vector;
   public ]b4_parser_class[(]b4_parse_param_decl([b4_lex_param_decl])[)]b4_maybe_throws([b4_init_throws])[
   {
 ]b4_percent_code_get([[init]])[]b4_lac_if([[
-    this.yylacStack = new Vector<Integer>();
+    this.yylacStack = new ArrayList<Integer>();
     this.yylacEstablished = false;]])[
     this.yylexer = new YYLexer(]b4_lex_param_call[);
 ]b4_parse_param_cons[
@@ -282,7 +282,7 @@ import java.util.Vector;
   ]b4_lexer_if([[protected]], [[public]]) b4_parser_class[(]b4_parse_param_decl([[Lexer yylexer]])[)]b4_maybe_throws([b4_init_throws])[
   {
 ]b4_percent_code_get([[init]])[]b4_lac_if([[
-    this.yylacStack = new Vector<Integer>();
+    this.yylacStack = new ArrayList<Integer>();
     this.yylacEstablished = false;]])[
     this.yylexer = yylexer;
 ]b4_parse_param_cons[
@@ -852,7 +852,7 @@ b4_dollar_popdef[]dnl
     this.yylen = 0;
     this.yystate = 0;
     this.yystack = new YYStack();]b4_lac_if([[
-    this.yylacStack = new Vector<Integer>();
+    this.yylacStack = new ArrayList<Integer>();
     this.yylacEstablished = false;]])[
     this.label = YYNEWSTATE;
 
@@ -1021,7 +1021,7 @@ b4_dollar_popdef[]dnl
         {
           int topState = (yylacStack.isEmpty()
                           ? yystack.stateAt(lacTop)
-                          : yylacStack.lastElement());
+                          : yylacStack.get(yylacStack.size() - 1));
           int yyrule = yypact_[topState];
           if (yyPactValueIsDefault(yyrule)
               || (yyrule += yytoken.getCode()) < 0 || YYLAST_ < yyrule
@@ -1056,7 +1056,10 @@ b4_dollar_popdef[]dnl
             // First pop from the LAC stack as many tokens as possible.
             int lacSize = yylacStack.size();
             if (yylen < lacSize) {
-              yylacStack.setSize(lacSize - yylen);
+              // yylacStack.setSize(lacSize - yylen);
+              for (/* Nothing */; 0 < yylen; yylen -= 1) {
+                yylacStack.remove(yylacStack.size() - 1);
+              }
               yylen = 0;
             } else if (lacSize != 0) {
               yylacStack.clear();
@@ -1069,7 +1072,7 @@ b4_dollar_popdef[]dnl
           // Keep topState in sync with the updated stack.
           topState = (yylacStack.isEmpty()
                       ? yystack.stateAt(lacTop)
-                      : yylacStack.lastElement());
+                      : yylacStack.get(yylacStack.size() - 1));
           // Push the resulting state of the reduction.
           int state = yyLRGotoState(topState, yyr1_[yyrule]);
           yycdebugNnl(" G" + state);
@@ -1139,7 +1142,7 @@ b4_dollar_popdef[]dnl
      * yylacCheck. We just store it as a member of this class to hold
      * on to the memory and to avoid frequent reallocations.
      */
-    Vector<Integer> yylacStack;
+    ArrayList<Integer> yylacStack;
     /**  Whether an initial LAC context was established. */
     boolean yylacEstablished;
 ]])[