How to use

MigrateToV2

in

co.cask.wrangler.parser

public static String getNextToken(StringTokenizer tokenizer, String delimiter,
                 String directive, String field, int lineno) throws DirectiveParseException {
 return getNextToken(tokenizer, delimiter, directive, field, lineno, false);
}

  String column = getNextToken(tokenizer, "set column", "column-name", lineno);
  String expr = getNextToken(tokenizer, "\n", "set column", "jexl-expression", lineno);
  transformed.add(String.format("set-column %s exp:{%s};", col(column), expr));
  String columns = getNextToken(tokenizer, "\n", "set columns", "name1, name2, ...", lineno);
  String cols[] = columns.split(",");
  transformed.add(String.format("set-headers %s;", toColumArray(cols)));
String oldcol = getNextToken(tokenizer,  command, "old", lineno);
String newcol = getNextToken(tokenizer, command, "new", lineno);
transformed.add(String.format("rename %s %s;", col(oldcol), col(newcol)));
String col = getNextToken(tokenizer,  command, "col", lineno);
String type = getNextToken(tokenizer, command, "type", lineno);
transformed.add(String.format("set-type %s %s;", col(col), type));
String columns = getNextToken(tokenizer, command, "column", lineno);
String cols[] = columns.split(",");
transformed.add(String.format("drop %s;", toColumArray(cols)));
String col1 = getNextToken(tokenizer, command, "first", lineno);
String col2 = getNextToken(tokenizer, command, "second", lineno);
String dest = getNextToken(tokenizer, command, "new-column", lineno);
String delimiter = getNextToken(tokenizer, "\n", command, "delimiter", lineno);
transformed.add(String.format("merge %s %s %s %s;", col(col1), col(col2), col(dest), quote(delimiter)));
String col = getNextToken(tokenizer, command, "col", lineno);
transformed.add(String.format("uppercase %s;", col(col)));

public RecipePipeline compile(List<String> recipe)
 throws RecipeException, DirectiveParseException, DirectiveLoadException, DirectiveNotFoundException {
 // Support only in-built directives.
 CompositeDirectiveRegistry registry = new CompositeDirectiveRegistry(
  new SystemDirectiveRegistry()
 );
 String migrate = new MigrateToV2(recipe).migrate();
 RecipeParser parser = new GrammarBasedParser(migrate, registry);
 parser.initialize(null); // No Directive Context.
 RecipePipeline pipeline = new RecipePipelineExecutor();
 pipeline.initialize(parser, context);
 return pipeline;
}

private static String toColumArray(String[] columns) {
 List<String> array = new ArrayList<>();
 for (String column : columns) {
  array.add(col(trim(column)));
 }
 return Joiner.on(",").join(array);
}

public static String getNextToken(StringTokenizer tokenizer, String directive,
                 String field, int lineno) throws DirectiveParseException {
 return getNextToken(tokenizer, null, directive, field, lineno, false);
}