/***********************************************************************************************************************
* Copyright (C) 2010-2013 by the Stratosphere project (http://stratosphere.eu)
*
* 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 eu.stratosphere.api.java.tuple;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Scanner;
import com.google.common.base.Charsets;
import com.google.common.io.Files;
/**
* Source code generator for tuple classes and classes which depend on the arity
* of tuples.
*/
class TupleGenerator {
// Parameters for tuple classes
private static final String ROOT_DIRECTORY = "./src/main/java";
private static final String PACKAGE = "eu.stratosphere.api.java.tuple";
private static final String BUILDER_SUFFIX = "builder";
private static final String GEN_TYPE_PREFIX = "T";
// Parameters for tuple-dependent classes
private static final String BEGIN_INDICATOR = "BEGIN_OF_TUPLE_DEPENDENT_CODE";
private static final String END_INDICATOR = "END_OF_TUPLE_DEPENDENT_CODE";
// Parameters for CsvReader
private static final String CSV_READER_PACKAGE = "eu.stratosphere.api.java.io";
private static final String CSV_READER_CLASSNAME = "CsvReader";
// Parameters for TupleTypeInfo
private static final String TUPLE_TYPE_INFO_PACKAGE = "eu.stratosphere.api.java.typeutils";
private static final String TUPLE_TYPE_INFO_CLASSNAME = "TupleTypeInfo";
// Parameters for ProjectOperator
private static final String PROJECT_OPERATOR_PACKAGE = "eu.stratosphere.api.java.operators";
private static final String PROJECT_OPERATOR_CLASSNAME = "ProjectOperator";
// Parameters for JoinOperator
private static final String JOIN_OPERATOR_PACKAGE = "eu.stratosphere.api.java.operators";
private static final String JOIN_OPERATOR_CLASSNAME = "JoinOperator";
// parameters for CrossOperator
private static final String CROSS_OPERATOR_PACKAGE = "eu.stratosphere.api.java.operators";
private static final String CROSS_OPERATOR_CLASSNAME = "CrossOperator";
// min. and max. tuple arity
private static final int FIRST = 1;
private static final int LAST = 25;
public static void main(String[] args) throws Exception {
File root = new File(ROOT_DIRECTORY);
createTupleClasses(root);
createTupleBuilderClasses(root);
modifyCsvReader(root);
modifyTupleTypeInfo(root);
modifyProjectOperator(root);
modifyJoinProjectOperator(root);
modifyCrossProjectOperator(root);
}
private static File getPackage(File root, String packageString) {
File dir = new File(root, packageString.replace('.', '/'));
if (!dir.exists() && dir.isDirectory()) {
System.err.println("None existent directory: " + dir.getAbsolutePath());
System.exit(1);
}
return dir;
}
private static void insertCodeIntoFile(String code, File file) throws IOException {
String fileContent = Files.toString(file, Charsets.UTF_8);
Scanner s = new Scanner(fileContent);
StringBuilder sb = new StringBuilder();
String line = null;
boolean indicatorFound = false;
// add file beginning
while (s.hasNextLine() && (line = s.nextLine()) != null) {
sb.append(line + "\n");
if (line.contains(BEGIN_INDICATOR)) {
indicatorFound = true;
break;
}
}
if(!indicatorFound) {
System.out.println("No indicator found in '" + file + "'. Will skip code generation.");
s.close();
return;
}
// add generator signature
sb.append("\t// GENERATED FROM " + TupleGenerator.class.getName() + ".\n");
// add tuple dependent code
sb.append(code + "\n");
// skip generated code
while (s.hasNextLine() && (line = s.nextLine()) != null) {
if (line.contains(END_INDICATOR)) {
sb.append(line + "\n");
break;
}
}
// add file ending
while (s.hasNextLine() && (line = s.nextLine()) != null) {
sb.append(line + "\n");
}
s.close();
Files.write(sb.toString(), file, Charsets.UTF_8);
}
private static void modifyCrossProjectOperator(File root) throws IOException {
// generate code
StringBuilder sb = new StringBuilder();
for (int numFields = FIRST; numFields <= LAST; numFields++) {
// method begin
sb.append("\n");
// method comment
sb.append("\t\t/**\n");
sb.append("\t\t * Projects a pair of crossed elements to a {@link Tuple} with the previously selected fields. \n");
sb.append("\t\t * Requires the classes of the fields of the resulting tuples. \n");
sb.append("\t\t * \n");
for (int i = 0; i < numFields; i++) {
sb.append("\t\t * @param type" + i + " The class of field '"+i+"' of the result tuples.\n");
}
sb.append("\t\t * @return The projected data set.\n");
sb.append("\t\t * \n");
sb.append("\t\t * @see Tuple\n");
sb.append("\t\t * @see DataSet\n");
sb.append("\t\t */\n");
// method signature
sb.append("\t\tpublic <");
appendTupleTypeGenerics(sb, numFields);
sb.append("> ProjectCross<I1, I2, Tuple"+numFields+"<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">> types(");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
sb.append(", ");
}
sb.append("Class<");
sb.append(GEN_TYPE_PREFIX + i);
sb.append("> type" + i);
}
sb.append(") {\n");
// convert type0..1 to types array
sb.append("\t\t\tClass<?>[] types = {");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
sb.append(", ");
}
sb.append("type" + i);
}
sb.append("};\n");
// check number of types and extract field types
sb.append("\t\t\tif(types.length != this.fieldIndexes.length) {\n");
sb.append("\t\t\t\tthrow new IllegalArgumentException(\"Numbers of projected fields and types do not match.\");\n");
sb.append("\t\t\t}\n");
sb.append("\t\t\t\n");
sb.append("\t\t\tTypeInformation<?>[] fTypes = extractFieldTypes(fieldIndexes, types);\n");
// create new tuple type info
sb.append("\t\t\tTupleTypeInfo<Tuple"+numFields+"<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">> tType = new TupleTypeInfo<Tuple"+numFields+"<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">>(fTypes);\n\n");
// create and return new project operator
sb.append("\t\t\treturn new ProjectCross<I1, I2, Tuple"+numFields+"<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">>(this.ds1, this.ds2, this.fieldIndexes, this.isFieldInFirst, tType);\n");
// method end
sb.append("\t\t}\n");
}
// insert code into file
File dir = getPackage(root, CROSS_OPERATOR_PACKAGE);
File projectOperatorClass = new File(dir, CROSS_OPERATOR_CLASSNAME + ".java");
insertCodeIntoFile(sb.toString(), projectOperatorClass);
}
private static void modifyProjectOperator(File root) throws IOException {
// generate code
StringBuilder sb = new StringBuilder();
for (int numFields = FIRST; numFields <= LAST; numFields++) {
// method begin
sb.append("\n");
// method comment
sb.append("\t\t/**\n");
sb.append("\t\t * Projects a {@link Tuple} {@link DataSet} to the previously selected fields. \n");
sb.append("\t\t * Requires the classes of the fields of the resulting Tuples. \n");
sb.append("\t\t * \n");
for (int i = 0; i < numFields; i++) {
sb.append("\t\t * @param type" + i + " The class of field '"+i+"' of the result Tuples.\n");
}
sb.append("\t\t * @return The projected DataSet.\n");
sb.append("\t\t * \n");
sb.append("\t\t * @see Tuple\n");
sb.append("\t\t * @see DataSet\n");
sb.append("\t\t */\n");
// method signature
sb.append("\t\tpublic <");
appendTupleTypeGenerics(sb, numFields);
sb.append("> ProjectOperator<T, Tuple"+numFields+"<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">> types(");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
sb.append(", ");
}
sb.append("Class<");
sb.append(GEN_TYPE_PREFIX + i);
sb.append("> type" + i);
}
sb.append(") {\n");
// convert type0..1 to types array
sb.append("\t\t\tClass<?>[] types = {");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
sb.append(", ");
}
sb.append("type" + i);
}
sb.append("};\n");
// check number of types and extract field types
sb.append("\t\t\tif(types.length != this.fieldIndexes.length) {\n");
sb.append("\t\t\t\tthrow new IllegalArgumentException(\"Numbers of projected fields and types do not match.\");\n");
sb.append("\t\t\t}\n");
sb.append("\t\t\t\n");
sb.append("\t\t\tTypeInformation<?>[] fTypes = extractFieldTypes(fieldIndexes, types, ds.getType());\n");
// create new tuple type info
sb.append("\t\t\tTupleTypeInfo<Tuple"+numFields+"<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">> tType = new TupleTypeInfo<Tuple"+numFields+"<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">>(fTypes);\n\n");
// create and return new project operator
sb.append("\t\t\treturn new ProjectOperator<T, Tuple"+numFields+"<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">>(this.ds, this.fieldIndexes, tType);\n");
// method end
sb.append("\t\t}\n");
}
// insert code into file
File dir = getPackage(root, PROJECT_OPERATOR_PACKAGE);
File projectOperatorClass = new File(dir, PROJECT_OPERATOR_CLASSNAME + ".java");
insertCodeIntoFile(sb.toString(), projectOperatorClass);
}
private static void modifyJoinProjectOperator(File root) throws IOException {
// generate code
StringBuilder sb = new StringBuilder();
for (int numFields = FIRST; numFields <= LAST; numFields++) {
// method begin
sb.append("\n");
// method comment
sb.append("\t\t/**\n");
sb.append("\t\t * Projects a pair of joined elements to a {@link Tuple} with the previously selected fields. \n");
sb.append("\t\t * Requires the classes of the fields of the resulting tuples. \n");
sb.append("\t\t * \n");
for (int i = 0; i < numFields; i++) {
sb.append("\t\t * @param type" + i + " The class of field '"+i+"' of the result tuples.\n");
}
sb.append("\t\t * @return The projected data set.\n");
sb.append("\t\t * \n");
sb.append("\t\t * @see Tuple\n");
sb.append("\t\t * @see DataSet\n");
sb.append("\t\t */\n");
// method signature
sb.append("\t\tpublic <");
appendTupleTypeGenerics(sb, numFields);
sb.append("> ProjectJoin<I1, I2, Tuple"+numFields+"<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">> types(");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
sb.append(", ");
}
sb.append("Class<");
sb.append(GEN_TYPE_PREFIX + i);
sb.append("> type" + i);
}
sb.append(") {\n");
// convert type0..1 to types array
sb.append("\t\t\tClass<?>[] types = {");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
sb.append(", ");
}
sb.append("type" + i);
}
sb.append("};\n");
// check number of types and extract field types
sb.append("\t\t\tif(types.length != this.fieldIndexes.length) {\n");
sb.append("\t\t\t\tthrow new IllegalArgumentException(\"Numbers of projected fields and types do not match.\");\n");
sb.append("\t\t\t}\n");
sb.append("\t\t\t\n");
sb.append("\t\t\tTypeInformation<?>[] fTypes = extractFieldTypes(fieldIndexes, types);\n");
// create new tuple type info
sb.append("\t\t\tTupleTypeInfo<Tuple"+numFields+"<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">> tType = new TupleTypeInfo<Tuple"+numFields+"<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">>(fTypes);\n\n");
// create and return new project operator
sb.append("\t\t\treturn new ProjectJoin<I1, I2, Tuple"+numFields+"<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">>(this.ds1, this.ds2, this.keys1, this.keys2, this.hint, this.fieldIndexes, this.isFieldInFirst, tType);\n");
// method end
sb.append("\t\t}\n");
}
// insert code into file
File dir = getPackage(root, JOIN_OPERATOR_PACKAGE);
File projectOperatorClass = new File(dir, JOIN_OPERATOR_CLASSNAME + ".java");
insertCodeIntoFile(sb.toString(), projectOperatorClass);
}
private static void modifyTupleTypeInfo(File root) throws IOException {
// generate code
StringBuilder sb = new StringBuilder();
sb.append("\tprivate static final Class<?>[] CLASSES = new Class<?>[] {\n\t\t");
for (int i = FIRST; i <= LAST; i++) {
if (i > FIRST) {
sb.append(", ");
}
sb.append("Tuple" + i + ".class");
}
sb.append("\n\t};");
// insert code into file
File dir = getPackage(root, TUPLE_TYPE_INFO_PACKAGE);
File tupleTypeInfoClass = new File(dir, TUPLE_TYPE_INFO_CLASSNAME + ".java");
insertCodeIntoFile(sb.toString(), tupleTypeInfoClass);
}
private static void modifyCsvReader(File root) throws IOException {
// generate code
StringBuilder sb = new StringBuilder(1000);
for (int numFields = FIRST; numFields <= LAST; numFields++) {
// method begin
sb.append("\n");
// java doc
sb.append("\t/**\n");
sb.append("\t * Specifies the types for the CSV fields. This method parses the CSV data to a ").append(numFields).append("-tuple\n");
sb.append("\t * which has fields of the specified types.\n");
sb.append("\t * This method is overloaded for each possible length of the tuples to support type safe\n");
sb.append("\t * creation of data sets through CSV parsing.\n");
sb.append("\t *\n");
for (int pos = 0; pos < numFields; pos++) {
sb.append("\t * @param type").append(pos);
sb.append(" The type of CSV field ").append(pos).append(" and the type of field ");
sb.append(pos).append(" in the returned tuple type.\n");
}
sb.append("\t * @return The {@link eu.stratosphere.api.java.DataSet} representing the parsed CSV data.\n");
sb.append("\t */\n");
// method signature
sb.append("\tpublic <");
appendTupleTypeGenerics(sb, numFields);
sb.append("> DataSource<Tuple" + numFields + "<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">> types(");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
sb.append(", ");
}
sb.append("Class<");
sb.append(GEN_TYPE_PREFIX + i);
sb.append("> type" + i);
}
sb.append(") {\n");
// get TupleTypeInfo
sb.append("\t\tTupleTypeInfo<Tuple" + numFields + "<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">> types = TupleTypeInfo.getBasicTupleTypeInfo(");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
sb.append(", ");
}
sb.append("type" + i);
}
sb.append(");\n");
// create csv input format
sb.append("\t\tCsvInputFormat<Tuple" + numFields + "<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">> inputFormat = new CsvInputFormat<Tuple" + numFields + "<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">>(path);\n");
// configure input format
sb.append("\t\tconfigureInputFormat(inputFormat, ");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
sb.append(", ");
}
sb.append("type" + i);
}
sb.append(");\n");
// return
sb.append("\t\treturn new DataSource<Tuple" + numFields + "<");
appendTupleTypeGenerics(sb, numFields);
sb.append(">>(executionContext, inputFormat, types);\n");
// end of method
sb.append("\t}\n");
}
// insert code into file
File dir = getPackage(root, CSV_READER_PACKAGE);
File csvReaderClass = new File(dir, CSV_READER_CLASSNAME + ".java");
insertCodeIntoFile(sb.toString(), csvReaderClass);
}
private static void appendTupleTypeGenerics(StringBuilder sb, int numFields) {
for (int i = 0; i < numFields; i++) {
if (i > 0) {
sb.append(", ");
}
sb.append(GEN_TYPE_PREFIX + i);
}
}
private static void createTupleClasses(File root) throws FileNotFoundException {
File dir = getPackage(root, PACKAGE);
for (int i = FIRST; i <= LAST; i++) {
File tupleFile = new File(dir, "Tuple" + i + ".java");
PrintWriter writer = new PrintWriter(tupleFile);
writeTupleClass(writer, i);
writer.flush();
writer.close();
}
}
private static void writeTupleClass(PrintWriter w, int numFields) {
final String className = "Tuple" + numFields;
// head
w.print(HEADER);
// package and imports
w.println("package " + PACKAGE + ';');
w.println();
w.println("import eu.stratosphere.util.StringUtils;");
w.println();
// class declaration and class comments
w.println("/**");
w.println(" * A tuple with " + numFields + " fields. Tuples are strongly typed; each field may be of a separate type.");
w.println(" * The fields of the tuple can be accessed directly as public fields (f0, f1, ...) or via their position");
w.println(" * through the {@link #getField(int)} method. The tuple field positions start at zero.");
w.println(" * <p>");
w.println(" * Tuples are mutable types, meaning that their fields can be re-assigned. This allows functions that work");
w.println(" * with Tuples to reuse objects in order to reduce pressure on the garbage collector.");
w.println(" *");
w.println(" * @see Tuple");
w.println(" *");
for (int i = 0; i < numFields; i++) {
w.println(" * @param <" + GEN_TYPE_PREFIX + i + "> The type of field " + i);
}
w.println(" */");
w.print("public class " + className + "<");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
w.print(", ");
}
w.print(GEN_TYPE_PREFIX + i);
}
w.println("> extends Tuple {");
w.println();
w.println("\tprivate static final long serialVersionUID = 1L;");
w.println();
// fields
for (int i = 0; i < numFields; i++) {
w.println("\t/** Field " + i + " of the tuple. */");
w.println("\tpublic " + GEN_TYPE_PREFIX + i + " f" + i + ';');
}
w.println();
// constructors
w.println("\t/**");
w.println("\t * Creates a new tuple where all fields are null.");
w.println("\t */");
w.println("\tpublic " + className + "() {}");
w.println();
w.println("\t/**");
w.println("\t * Creates a new tuple and assigns the given values to the tuple's fields.");
w.println("\t *");
for (int i = 0; i < numFields; i++) {
w.println("\t * @param value" + i + " The value for field " + i);
}
w.println("\t */");
w.print("\tpublic " + className + "(");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
w.print(", ");
}
w.print(GEN_TYPE_PREFIX + i + " value" + i);
}
w.println(") {");
for (int i = 0; i < numFields; i++) {
w.println("\t\tthis.f" + i + " = value" + i + ';');
}
w.println("\t}");
w.println();
// arity accessor
w.println("\t@Override");
w.println("\tpublic int getArity() { return " + numFields + "; }");
w.println();
// accessor getter method
w.println("\t@Override");
w.println("\t@SuppressWarnings(\"unchecked\")");
w.println("\tpublic <T> T getField(int pos) {");
w.println("\t\tswitch(pos) {");
for (int i = 0; i < numFields; i++) {
w.println("\t\t\tcase " + i + ": return (T) this.f" + i + ';');
}
w.println("\t\t\tdefault: throw new IndexOutOfBoundsException(String.valueOf(pos));");
w.println("\t\t}");
w.println("\t}");
w.println();
// accessor setter method
w.println("\t@Override");
w.println("\t@SuppressWarnings(\"unchecked\")");
w.println("\tpublic <T> void setField(T value, int pos) {");
w.println("\t\tswitch(pos) {");
for (int i = 0; i < numFields; i++) {
w.println("\t\t\tcase " + i + ':');
w.println("\t\t\t\tthis.f" + i + " = (" + GEN_TYPE_PREFIX + i + ") value;");
w.println("\t\t\t\tbreak;");
}
w.println("\t\t\tdefault: throw new IndexOutOfBoundsException(String.valueOf(pos));");
w.println("\t\t}");
w.println("\t}");
w.println();
// accessor setter method for all fields
w.println("\t/**");
w.println("\t * Sets new values to all fields of the tuple.");
w.println("\t *");
for (int i = 0; i < numFields; i++) {
w.println("\t * @param value" + i + " The value for field " + i);
}
w.println("\t */");
w.print("\tpublic void setFields(");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
w.print(", ");
}
w.print(GEN_TYPE_PREFIX + i + " value" + i);
}
w.println(") {");
for (int i = 0; i < numFields; i++) {
w.println("\t\tthis.f" + i + " = value" + i + ';');
}
w.println("\t}");
w.println();
// standard utilities (toString, equals, hashCode)
w.println();
w.println("\t// -------------------------------------------------------------------------------------------------");
w.println("\t// standard utilities");
w.println("\t// -------------------------------------------------------------------------------------------------");
w.println();
w.println("\t/**");
w.println("\t * Creates a string representation of the tuple in the form");
w.print("\t * (f0");
for (int i = 1; i < numFields; i++) {
w.print(", f" + i);
}
w.println("),");
w.println("\t * where the individual fields are the value returned by calling {@link Object#toString} on that field.");
w.println("\t * @return The string representation of the tuple.");
w.println("\t */");
w.println("\t@Override");
w.println("\tpublic String toString() {");
w.println("\t\treturn \"(\" + StringUtils.arrayAwareToString(this.f0)");
for (int i = 1; i < numFields; i++) {
w.println("\t\t\t+ \", \" + StringUtils.arrayAwareToString(this.f" + i + ")");
}
w.println("\t\t\t+ \")\";");
w.println("\t}");
// foot
w.println("}");
}
private static void createTupleBuilderClasses(File root) throws FileNotFoundException {
File dir = getPackage(root, PACKAGE+"."+BUILDER_SUFFIX);
for (int i = FIRST; i <= LAST; i++) {
File tupleFile = new File(dir, "Tuple" + i + "Builder.java");
PrintWriter writer = new PrintWriter(tupleFile);
writeTupleBuilderClass(writer, i);
writer.flush();
writer.close();
}
}
private static void printGenericsString(PrintWriter w, int numFields){
w.print("<");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
w.print(", ");
}
w.print(GEN_TYPE_PREFIX + i);
}
w.print(">");
}
private static void writeTupleBuilderClass(PrintWriter w, int numFields) {
final String className = "Tuple" + numFields + "Builder";
// head
w.print(HEADER);
// package and imports
w.println("package " + PACKAGE + "." + BUILDER_SUFFIX + ';');
w.println();
w.println("import java.util.LinkedList;");
w.println("import java.util.List;");
w.println();
w.println("import " + PACKAGE + ".Tuple" + numFields + ";");
w.println();
// class declaration
w.print("public class " + className);
printGenericsString(w, numFields);
w.println(" {");
w.println();
// Class-Attributes - a list of tuples
w.print("\tprivate List<Tuple" + numFields);
printGenericsString(w, numFields);
w.print("> tuples = new LinkedList<Tuple" + numFields );
printGenericsString(w, numFields);
w.println(">();");
w.println();
// add(...) function for adding a single tuple
w.print("\tpublic " + className);
printGenericsString(w, numFields);
w.print(" add(");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
w.print(", ");
}
w.print(GEN_TYPE_PREFIX + i + " value" + i);
}
w.println("){");
w.print("\t\ttuples.add(new Tuple" + numFields);
printGenericsString(w, numFields);
w.print("(");
for (int i = 0; i < numFields; i++) {
if (i > 0) {
w.print(", ");
}
w.print("value" + i);
}
w.println("));");
w.println("\t\treturn this;");
w.println("\t}");
w.println();
// build() function, returns an array of tuples
w.println("\t@SuppressWarnings(\"unchecked\")");
w.print("\tpublic Tuple" + numFields);
printGenericsString(w, numFields);
w.println("[] build(){");
w.println("\t\treturn tuples.toArray(new Tuple" + numFields + "[tuples.size()]);");
w.println("\t}");
// foot
w.println("}");
}
private static String HEADER =
"/***********************************************************************************************************************\n" +
" *\n" +
" * Copyright (C) 2010-2013 by the Stratosphere project (http://stratosphere.eu)\n" +
" *\n" +
" * Licensed under the Apache License, Version 2.0 (the \"License\"); you may not use this file except in compliance with\n" +
" * the License. You may obtain a copy of the License at\n" +
" *\n" +
" * http://www.apache.org/licenses/LICENSE-2.0\n" +
" *\n" +
" * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on\n" +
" * an \"AS IS\" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the\n" +
" * specific language governing permissions and limitations under the License.\n" +
" *\n" +
" **********************************************************************************************************************/\n" +
"\n" +
"// --------------------------------------------------------------\n" +
"// THIS IS A GENERATED SOURCE FILE. DO NOT EDIT!\n" +
"// GENERATED FROM " + TupleGenerator.class.getName() + ".\n" +
"// --------------------------------------------------------------\n\n\n";
}