Formatting simple tabular text data
This class has been posted first time on the Groovy-User Mailing List by Raffaele Castagno in this format:
class TableTemplateFactory
{
def columns = []; // contains columns names and theyr length
def header1 = ''; // contains columns names
def header2 = ''; // contains underscores
def body = ''; // the rows of the table
def footer = ''; // actually unused: can contain footer notes, totals, etc.
def addColumn(name, size)
{
columns << [name:name, size:size];
}
def getTemplate()
{
header1 = "\n";
columns.each{ header1 += ' <%print "'+it.name+'".center('+it.size+')%> ' };
header2 = "\n";
columns.each{ header2 += ' <%print "_"*'+it.size+' %> ' };
body = '\n<% rows.each {%>';
// If a value is longer than given column name, it will be trunked
columns.each{body += ' ${it.'+it.name+'.toString().padRight('+it.size+').substring(0,'+it.size+')} '};
body += '\n<% } %>';
return header1 + header2 + body + footer;
} }
and later "groovyfied" by Gavin Grover:
class TableTemplateFactory{
def columns = []
def addColumn(name, size) { columns << [name:name, size:size]; this }
def getTemplate() { """
${columns.collect{ " <%print \"$it.name\".center($it.size)%> " }.join()}
${columns.collect{ " <%print \"_\"*$it.size %> " }.join()}
<% rows.each {%>${columns.collect{ " \${it.${it.name}.toString().padRight($it.size).substring(0,$it.size)} " }.join()}
<% } %>"""
}
}
First version is here only as an example of the "groovify process". Of course, the Gavin's version is better.
This class emulate the output of most RDBMS consoles (ie. Oracle SQL*, MySql).
Here's an usage example (again, grooved up by Gavin):
import groovy.text.Template; import groovy.text.SimpleTemplateEngine def ttf = new TableTemplateFactory().addColumn("name", 15).addColumn("age", 4) def names = [] << [name:"Raffaele", age:"23"] << [name:"Griorgio", age:"30"] def binding = ['rows': names] println new SimpleTemplateEngine().createTemplate(ttf.template).make(binding).toString()
This is the output:
name age _______________ ____ Raffaele 23 Griorgio 30
Actually is really limited: column width must be declared, and strings are truncated to that given size.
