使用univocity-html-parser，您可以从此页面获取所有内容。
要获得你需要的元素，你不必太在意它的完整路径：
HtmlElement e = HtmlParser.parseTree(new UrlReaderProvider("http://www.dolarhoy.com/"));
String value = e.query()
.match("td").withText("$*") //match a <td> with any text starting with a $
.precededImmediatelyBy("td").withText("VENTA") //if found, it must have a <td> on its left, with text "VENTA"
.getText().getValue(); // if found, get the text of the the <td> and return the value as a String
这为我生成了 $ 28.17 的值。
现在，获取可用记录中所有表的所有值：
HtmlEntityList entityList = new HtmlEntityList();
HtmlEntitySettings currency = entityList.configureEntity("currency");
// removes rows with unwanted data
currency.addRecordFilter((record, context) -> isValidRecord(record));
//the group enables the matching rules to run only on tables that have text
//"compra" and "venta". We add fields to the group.
Group currencyTable = currency.newGroup().startAt("table").containing("tr").withText("*Compra ", "*Venta ").endAtClosing("table");
//the currency name and time are in the same table cell. The matching rule is the same for both "currency" and "timestamp" fields
addIdentifierField(currencyTable, "currency", 0);
addIdentifierField(currencyTable, "timestamp", 1);
//captures the currency exchange business name
currencyTable.addPersistentField("exchange").match("td").underHeaderAtRow("td", 3).withExactText("EN $").getText();
//captures the currency purchase and sale price
currencyTable.addField("buy").match("td").withText("?*").underHeaderAtRow("td", 3).withExactText("Compra").getText();
currencyTable.addField("sell").match("td").withText("?*").underHeaderAtRow("td", 3).withExactText("Venta").getText();
//additional matching rules to get the dollar prices listed in the first table (it has id = "table2")
currencyTable.addPersistentField("exchange").match("table").id("table2").match("tr").matchFirst("td").withText("?*").getText();
currencyTable.addField("buy").match("table").id("table2").match("td").withText("?*").underHeader("td").withExactText("Compra").getText();
currencyTable.addField("sell").match("table").id("table2").match("td").withText("?*").underHeader("td").withExactText("Venta").getText();
HtmlParser parser = new HtmlParser(entityList);
Results<HtmlParserResult> results = parser.parse(new UrlReaderProvider("http://www.dolarhoy.com/"));
HtmlParserResult result = results.get("currency");
for (HtmlRecord record : result.iterateRecords()) {
println(record.fillFieldMap(new LinkedHashMap<String, String>()));
}
其中方法addIdentifierField定义为：
private void addIdentifierField(Group table, String field, final int pos) {
//matches any <td> where the colspan attribute is 4, 5 or 6, then gets the text of the <b> element inside the <td>
table.addPersistentField(field).match("td").attribute("colspan", 4, 5, 6).match("b").getText().transform(s -> splitCurrencyAndTime(s)[pos]);
}
方法splitCurrencyAndTime：
// splits the currency and timestamp at the top of each table. Finds the first
// non-letter character after counting multiple whitespaces and splits the string in two
private String[] splitCurrencyAndTime(String value) {
int spaceCount = 0;
for (int i = 0; i < value.length(); i++) {
char ch = value.charAt(i);
if (ch == ' ') {
spaceCount++;
} else if (spaceCount > 0 && !Character.isLetter(ch) && ch != '$') {
String currency = value.substring(0, i).trim();
String timestamp = value.substring(i).trim();
return new String[]{currency, timestamp};
}
}
//if no match then just return nulls
return new String[2];
}
最后方法isValidRecord 防止删除诸如{currency=EURO, timestamp=15:35:39 HS. AR 10/08/18, exchange=MEJORES PRECIOS, buy=34.000, sell=34.702} 之类的结果：
private boolean isValidRecord(Record record){
String exchange = record.getString("exchange");
return exchange != null && !exchange.contains("MEJORES") && !exchange.contains("DolarHoy.com");
}
输出将是：
{currency=DÓLAR ESTADOUNIDENSE EN $, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe, buy=28.500, sell=29.500}
{currency=DÓLAR ESTADOUNIDENSE EN $, timestamp=15:35:39 HS. AR 10/08/18, exchange=Banco Nación, buy=28.700, sell=29.700}
{currency=DÓLAR ESTADOUNIDENSE EN $, timestamp=15:35:39 HS. AR 10/08/18, exchange=Montevideo Cambio, buy=28.000, sell=29.300}
{currency=EURO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Banco Nación, buy=34.000, sell=35.000}
{currency=EURO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=33.502, sell=34.702}
{currency=EURO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Montevideo Cambio S.A., buy=31.400, sell=35.200}
{currency=REAL, timestamp=15:35:39 HS. AR 10/08/18, exchange=Banco Nación, buy=7.0000, sell=8.0000}
{currency=REAL, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=6.8000, sell=7.4000}
{currency=REAL, timestamp=15:35:39 HS. AR 10/08/18, exchange=Montevideo Cambio S.A., buy=6.6000, sell=7.5000}
{currency=PESO URUGUAYO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=0.89060, sell=1.01720}
{currency=PESO URUGUAYO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Montevideo Cambio S.A., buy=0.75000, sell=1.00000}
{currency=PESO CHILENO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=0.04250, sell=0.05180}
{currency=PESO CHILENO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Montevideo Cambio S.A., buy=0.03600, sell=0.04600}
{currency=GUARANÍ, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=0.00440, sell=0.00590}
{currency=GUARANÍ, timestamp=15:35:39 HS. AR 10/08/18, exchange=Montevideo Cambio S.A., buy=0.00450, sell=0.00535}
{currency=FRANCO SUIZO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=24.7826, sell=31.0526}
{currency=FRANCO SUIZO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Montevideo Cambio S.A., buy=21.2000, sell=29.4000}
{currency=LIBRA ESTERLINA, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=38.7228, sell=41.7729}
{currency=LIBRA ESTERLINA, timestamp=15:35:39 HS. AR 10/08/18, exchange=Montevideo Cambio S.A., buy=35.4000, sell=44.3000}
{currency=YEN, timestamp=15:35:39 HS. AR 10/08/18, exchange=Montevideo Cambio S.A., buy=0.2456, sell=0.2745}
{currency=DÓLAR CANADIENSE, timestamp=15:35:39 HS. AR 10/08/18, exchange=Montevideo Cambio S.A., buy=18.950, sell=23.100}
{currency=PESO MEXICANO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Montevideo Cambio S.A., buy=1.500, sell=1.930}
{currency=DÓLAR AUSTRALIANO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Montevideo Cambio S.A., buy=15.150, sell=21.900}
{currency=LIBRA ORO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=7267.50, sell=9292.50}
{currency=KRUGER RAND, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=30780.00, sell=39235.00}
{currency=CHILENO DE ORO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=18097.50, sell=22715.00}
{currency=100 GRAMOS DE ORO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Banco Ciudad, buy=null, sell=110636.00}
{currency=100 GRAMOS DE ORO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=99180.00, sell=128325.00}
{currency=50 GRAMOS DE ORO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Banco Ciudad, buy=null, sell=55473.00}
{currency=50 GRAMOS DE ORO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=49590.00, sell=65195.00}
{currency=20 GRAMOS DE ORO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=19807.50, sell=25812.50}
{currency=10 GRAMOS DE ORO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Banco Ciudad, buy=null, sell=11343.00}
{currency=10 GRAMOS DE ORO, timestamp=15:35:39 HS. AR 10/08/18, exchange=Cambio Alpe S.A., buy=9975.00, sell=13275.00}
希望这对你有用。
披露：我是这个库的作者。它是商业封闭源代码，但可以为您节省大量开发时间。