com.davidbracewell.io.structured.csv.CSVWriter Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of mango Show documentation
Show all versions of mango Show documentation
A set of utilities and tools to speed up and ease programming in Java.
/*
* (c) 2005 David B. Bracewell
*
* 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 com.davidbracewell.io.structured.csv;
import com.davidbracewell.SystemInfo;
import com.davidbracewell.collection.Index;
import com.davidbracewell.collection.Indexes;
import com.davidbracewell.conversion.Cast;
import com.davidbracewell.conversion.Convert;
import com.davidbracewell.io.CSV;
import com.davidbracewell.io.structured.StructuredWriter;
import com.davidbracewell.io.structured.Writable;
import com.davidbracewell.string.CSVFormatter;
import com.davidbracewell.string.StringUtils;
import com.google.common.base.Preconditions;
import lombok.NonNull;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.Writer;
import java.util.Collection;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.stream.Collectors;
import java.util.stream.Stream;
/**
* Wraps writing collections and maps in DSV format to resources.
*
* @author David B. Bracewell
*/
public class CSVWriter extends StructuredWriter {
private final CSVFormatter formatter;
private final BufferedWriter writer;
private boolean endOfDocument = false;
private Index header = Indexes.newIndex();
private Map row = new LinkedHashMap<>();
public CSVWriter(@NonNull CSV csv, @NonNull Writer writer) throws IOException {
this.formatter = csv.formatter();
this.writer = new BufferedWriter(writer);
if (csv.getHeader() != null && !csv.getHeader().isEmpty()) {
writer.write(formatter.format(csv.getHeader()));
writer.write(SystemInfo.LINE_SEPARATOR);
header.addAll(csv.getHeader());
}
}
/**
* Writes the items in the row to the resource in DSV format.
*
* @param row the row
* @throws IOException Signals that an I/O exception has occurred.
*/
public void write(Iterable row) throws IOException {
if (row != null) {
writer.write(formatter.format(row));
}
writer.write(SystemInfo.LINE_SEPARATOR);
}
/**
* Writes the items in the row to the resource in DSV format.
*
* @param row the row
* @throws IOException Signals that an I/O exception has occurred.
*/
public void write(Iterator row) throws IOException {
if (row != null) {
writer.write(formatter.format(row));
}
writer.write(SystemInfo.LINE_SEPARATOR);
}
/**
* Writes the items in the row to the resource in DSV format.
*
* @param row the row
* @throws IOException Signals that an I/O exception has occurred.
*/
public void write(Map row) throws IOException {
if (row != null) {
if (header.isEmpty()) {
for (Map.Entry m : row.entrySet()) {
writer.write(formatter.format(Convert.convert(m.getKey(), String.class), Convert.convert(m.getValue(), String.class)));
writer.write(SystemInfo.LINE_SEPARATOR);
}
} else {
writer.write(
formatter.format(
Stream.concat(
header.asList().stream()
.map(h -> row.containsKey(h) ? Convert.convert(row.get(h), String.class) : StringUtils.EMPTY),
row.keySet().stream()
.map(k -> Convert.convert(k, String.class))
.filter(h -> !header.contains(h))
.map(h -> Convert.convert(row.get(h), String.class))
)
.collect(Collectors.toList())
)
);
writer.write(SystemInfo.LINE_SEPARATOR);
}
}
}
/**
* Writes the items in the row to the resource in DSV format.
*
* @param row the row
* @param keyValueSeparator the character to use to separate keys and values
* @throws IOException Signals that an I/O exception has occurred.
*/
public void write(Map row, char keyValueSeparator) throws IOException {
if (row != null) {
if (header.isEmpty()) {
writer.write(formatter.format(row, keyValueSeparator));
} else {
writer.write(
formatter.format(
Stream.concat(
header.asList().stream()
.map(h -> row.containsKey(h) ? Convert.convert(row.get(h), String.class) : StringUtils.EMPTY),
row.keySet().stream()
.map(k -> Convert.convert(k, String.class))
.filter(h -> !header.contains(h))
.map(h -> Convert.convert(row.get(h), String.class))
)
.collect(Collectors.toList())
)
);
}
}
writer.write(SystemInfo.LINE_SEPARATOR);
}
/**
* Writes the items in the row to the resource in DSV format.
*
* @param row the row
* @throws IOException Signals that an I/O exception has occurred.
*/
public void write(Object... row) throws IOException {
if (row != null) {
writer.write(formatter.format(row));
}
writer.write(SystemInfo.LINE_SEPARATOR);
}
@Override
public void close() throws IOException {
writer.close();
}
@Override
public void flush() throws IOException {
writer.flush();
}
@Override
public StructuredWriter beginDocument(boolean isArray) throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
return this;
}
@Override
public void endDocument() throws IOException {
if (row.size() > 0) {
write(row);
}
endOfDocument = true;
}
@Override
public StructuredWriter beginObject(String name) throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
return this;
}
@Override
public StructuredWriter beginObject() throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
return this;
}
@Override
public StructuredWriter endObject() throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
write(row);
row.clear();
return this;
}
@Override
public StructuredWriter beginArray(String name) throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
return this;
}
@Override
public StructuredWriter beginArray() throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
return this;
}
@Override
public StructuredWriter endArray() throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
write(row);
row.clear();
return this;
}
@Override
public boolean inArray() {
return true;
}
@Override
public boolean inObject() {
return true;
}
@Override
public StructuredWriter writeValue(Object value) throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
if (value instanceof Writable) {
Cast.as(value).write(this);
} else {
row.put("___UNNAMED___[" + row.size() + "]", value);
}
return this;
}
@Override
protected StructuredWriter writeObject(@NonNull Object value) throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
if (value instanceof Writable) {
Cast.as(value).write(this);
} else {
row.put("___UNNAMED___[" + row.size() + "]", value);
}
return this;
}
@Override
protected StructuredWriter writeMap(@NonNull Map map) throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
map.entrySet().forEach(entry ->
row.put(Convert.convert(entry.getKey(), String.class), Convert.convert(entry.getValue(), String.class))
);
return this;
}
@Override
protected StructuredWriter writeCollection(@NonNull Collection collection) throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
collection.forEach(value ->
row.put("___UNNAMED___[" + row.size() + "]", value)
);
return this;
}
@Override
protected StructuredWriter writeArray(@NonNull Object[] array) throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
for (Object value : array) {
row.put("___UNNAMED___[" + row.size() + "]", value);
}
return this;
}
@Override
public StructuredWriter writeKeyValue(String key, Object value) throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
if (value instanceof Writable) {
Cast.as(value).write(this);
} else {
row.put(key, value);
}
return this;
}
@Override
protected StructuredWriter writeNull() throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
row.put("___UNNAMED___[" + row.size() + "]", null);
return this;
}
@Override
protected StructuredWriter writeNumber(Number number) throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
row.put("___UNNAMED___[" + row.size() + "]", number.toString());
return this;
}
@Override
protected StructuredWriter writeString(String string) throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
row.put("___UNNAMED___[" + row.size() + "]", string);
return this;
}
@Override
protected StructuredWriter writeBoolean(boolean value) throws IOException {
Preconditions.checkState(!endOfDocument, "endDocument() has been called");
row.put("___UNNAMED___[" + row.size() + "]", Boolean.toString(value));
return this;
}
}//END OF CSVWriter
© 2015 - 2025 Weber Informatics LLC | Privacy Policy