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Format examples for fluent style

This commit is contained in:
Gary Gregory 2023-05-01 08:57:23 -04:00
parent 0bcdcfd466
commit 4ca0556f6b
1 changed files with 30 additions and 15 deletions
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45
src/site/xdoc/user-guide.xml
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@ -71,24 +71,23 @@ for (CSVRecord record : records) {
for example: for example:
</p> </p>
<source>final URL url = ...; <source>final URL url = ...;
final Reader reader = new InputStreamReader(new BOMInputStream(url.openStream()), "UTF-8"); try (final Reader reader = new InputStreamReader(new BOMInputStream(url.openStream()), "UTF-8");
final CSVParser parser = CSVFormat.EXCEL.builder().setHeader().build().parse(reader); final CSVParser parser = CSVFormat.EXCEL.builder()
try { .setHeader()
.build()
.parse(reader)) {
for (final CSVRecord record : parser) { for (final CSVRecord record : parser) {
final String string = record.get("SomeColumn"); final String string = record.get("SomeColumn");
... ...
} }
} finally {
parser.close();
reader.close();
} }
</source> </source>
<p> <p>
You might find it handy to create something like this: You might find it handy to create something like this:
</p> </p>
<source>/** <source>/**
* Creates a reader capable of handling BOMs. * Creates a reader capable of handling BOMs.
*/ */
public InputStreamReader newReader(final InputStream inputStream) { public InputStreamReader newReader(final InputStream inputStream) {
return new InputStreamReader(new BOMInputStream(inputStream), StandardCharsets.UTF_8); return new InputStreamReader(new BOMInputStream(inputStream), StandardCharsets.UTF_8);
} }
@ -118,7 +117,10 @@ for (CSVRecord record : records) {
Indices may not be the most intuitive way to access record values. For this reason it is possible to Indices may not be the most intuitive way to access record values. For this reason it is possible to
assign names to each column in the file: assign names to each column in the file:
<source>Reader in = new FileReader(&quot;path/to/file.csv&quot;); <source>Reader in = new FileReader(&quot;path/to/file.csv&quot;);
Iterable&lt;CSVRecord&gt; records = CSVFormat.RFC4180.builder().setHeader("ID", "CustomerNo", "Name").build().parse(in); Iterable&lt;CSVRecord&gt; records = CSVFormat.RFC4180.builder()
.setHeader("ID", "CustomerNo", "Name")
.build()
.parse(in);
for (CSVRecord record : records) { for (CSVRecord record : records) {
String id = record.get("ID"); String id = record.get("ID");
String customerNo = record.get("CustomerNo"); String customerNo = record.get("CustomerNo");
@ -136,7 +138,10 @@ for (CSVRecord record : records) {
ID, CustomerNo, Name ID, CustomerNo, Name
} }
Reader in = new FileReader(&quot;path/to/file.csv&quot;); Reader in = new FileReader(&quot;path/to/file.csv&quot;);
Iterable&lt;CSVRecord&gt; records = CSVFormat.RFC4180.builder().setHeader(Headers.class).build().parse(in); Iterable&lt;CSVRecord&gt; records = CSVFormat.RFC4180.builder()
.setHeader(Headers.class)
.build()
.parse(in);
for (CSVRecord record : records) { for (CSVRecord record : records) {
String id = record.get(Headers.ID); String id = record.get(Headers.ID);
String customerNo = record.get(Headers.CustomerNo); String customerNo = record.get(Headers.CustomerNo);
@ -149,7 +154,11 @@ for (CSVRecord record : records) {
Some CSV files define header names in their first record. If configured, Apache Commons CSV can parse Some CSV files define header names in their first record. If configured, Apache Commons CSV can parse
the header names from the first record: the header names from the first record:
<source>Reader in = new FileReader(&quot;path/to/file.csv&quot;); <source>Reader in = new FileReader(&quot;path/to/file.csv&quot;);
Iterable&lt;CSVRecord&gt; records = CSVFormat.RFC4180.builder().setHeader().setSkipHeaderRecord(true).build().parse(in); Iterable&lt;CSVRecord&gt; records = CSVFormat.RFC4180.builder()
.setHeader()
.setSkipHeaderRecord(true)
.build()
.parse(in);
for (CSVRecord record : records) { for (CSVRecord record : records) {
String id = record.get("ID"); String id = record.get("ID");
String customerNo = record.get("CustomerNo"); String customerNo = record.get("CustomerNo");
@ -163,16 +172,22 @@ for (CSVRecord record : records) {
To print a CSV file with headers, you specify the headers in the format: To print a CSV file with headers, you specify the headers in the format:
</p> </p>
<source>final Appendable out = ...; <source>final Appendable out = ...;
final CSVPrinter printer = CSVFormat.DEFAULT.builder().setHeader("H1", "H2").build().print(out); final CSVPrinter printer = CSVFormat.DEFAULT.builder()
.setHeader("H1", "H2")
.build()
.print(out);
</source> </source>
<p> <p>
To print a CSV file with JDBC column labels, you specify the ResultSet in the format: To print a CSV file with JDBC column labels, you specify the ResultSet in the format:
</p> </p>
<source>final ResultSet resultSet = ...; <source>try (final ResultSet resultSet = ...) {
final CSVPrinter printer = CSVFormat.DEFAULT.builder().setHeader(resultSet).build().print(out); final CSVPrinter printer = CSVFormat.DEFAULT.builder()
.setHeader(resultSet)
.build()
.print(out);
}
</source> </source>
</subsection> </subsection>
</section> </section>
<!-- ================================================== -->
</body> </body>
</document> </document>