Capture HTML Tables from Websites with Java

There are multiple ways of converting HTML tables into JSON, CSV's and Excel spreadsheets using GrabzIt's Java API, detailed here are some of the most useful techniques. However before you start remember that after calling the URLToTable, HTMLToTable or FileToTable methods the Save or SaveTo method must be called to capture the table. If you want to quickly see if this service is right for you, you can try a live demo of capturing HTML tables from a URL.

Basic Options

This code snippet will convert the first HTML table found in a specified webpage into a CSV document.

URL to Table
HTML to Table
File to Table

grabzIt.URLToTable("https://www.tesla.com");
//Then call the Save or SaveTo method

grabzIt.HTMLToTable("<html><body><table><tr><th>Name</th><th>Age</th></tr>
    <tr><td>Tom</td><td>23</td></tr><tr><td>Nicola</td><td>26</td></tr>
    </table></body></html>");
//Then call the Save or SaveTo method

grabzIt.FileToTable("tables.html");
//Then call the Save or SaveTo method

By default this will convert the first table it identifies into a table. However the the second table in a web page could be converted by passing a 2 to the setTableNumberToInclude method of the TableOptions class.

URL to Table
HTML to Table
File to Table

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setTableNumberToInclude(2);

grabzIt.URLToTable("https://www.tesla.com", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.csv");

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setTableNumberToInclude(2);

grabzIt.HTMLToTable("<html><body><table><tr><th>Name</th><th>Age</th></tr>
    <tr><td>Tom</td><td>23</td></tr><tr><td>Nicola</td><td>26</td></tr>
    </table></body></html>", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.csv");

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setTableNumberToInclude(2);

grabzIt.FileToTable("tables.html", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.csv");

You can also use the setTargetElement method to ensure that only tables within the specified element id will be converted.

URL to Table
HTML to Table
File to Table

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setTargetElement("stocks_table");

grabzIt.URLToTable("https://www.tesla.com", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.csv");

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setTargetElement("stocks_table");

grabzIt.HTMLToTable("<html><body><table id='stocks_table'><tr><th>Name</th><th>Age</th></tr>
    <tr><td>Tom</td><td>23</td></tr><tr><td>Nicola</td><td>26</td></tr>
    </table></body></html>", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.csv");

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setTargetElement("stocks_table");

grabzIt.FileToTable("tables.html", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.csv");

Alternatively you can capture all tables on a web page by passing true to the setIncludeAllTables method, however this will only work with the XLSX and JSON formats. This option will put each table in a new sheet within the generated spreadsheet workbook.

URL to Table
HTML to Table
File to Table

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setFormat(TableFormat.XLSX);
options.setIncludeAllTables(true);

grabzIt.URLToTable("https://www.tesla.com", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.xlsx");

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setFormat(TableFormat.XLSX);
options.setIncludeAllTables(true);

grabzIt.HTMLToTable("<html><body><table><tr><th>Name</th><th>Age</th></tr>
    <tr><td>Tom</td><td>23</td></tr><tr><td>Nicola</td><td>26</td></tr>
    </table></body></html>", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.xlsx");

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setFormat(TableFormat.XLSX);
options.setIncludeAllTables(true);

grabzIt.FileToTable("tables.html", options);
//Then call the Save or SaveTo method
grabzIt.SaveTo("result.xlsx");

Convert HTML Tables to JSON

GrabzIt can also convert HTML tables found on the web to JSON, just specify the JSON format instead. In the example below the data is read synchronously and is returned as a GrabzItFile object by using the SaveTo method, however it is generally recommended that you do this asynchronously.

When the conversion is completed the toString method is called to get the JSON as a string, this can be then parsed by a library like google gson.

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setFormat(TableFormat.JSON);
options.setTableNumberToInclude(1);

grabzIt.URLToTable("https://www.tesla.com", options);

GrabzItFile file = grabzIt.SaveTo();
if (file != null)
{
    String json = file.toString();
}

Custom Identifier

You can pass a custom identifier to the table methods as shown below, this value is then returned to your GrabzIt Java handler. For instance this custom identifier could be a database identifier, allowing a screenshot to be associated with a particular database record.

URL to Table
HTML to Table
File to Table

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setCustomId("123456");

grabzIt.URLToTable("https://www.tesla.com", options);
//Then call the Save method
grabzIt.Save("http://www.example.com/handler");

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setCustomId("123456");

grabzIt.HTMLToTable("<html><body><h1>Hello World!</h1></body></html>", options);
//Then call the Save method
grabzIt.Save("http://www.example.com/handler");

GrabzItClient grabzIt = new GrabzItClient("Sign in to view your Application Key", "Sign in to view your Application Secret");

TableOptions options = new TableOptions();
options.setCustomId("123456");

grabzIt.FileToTable("example.html", options);
//Then call the Save method
grabzIt.Save("http://www.example.com/handler");