JarCastingrecord
A friendly heterogeneous map class for Java.
Examples
Import it:
import fun.mike.record;
Make a Record by passing alternating keys and values:
Record rec = Record.of("str", "bar",
"integ", 5,
"bigdec", new BigDecimal("1.0"),
"boole", true,
"long", 5L,
"list", Arrays.asList("foo", "bar"),
"map", new HashMap<>());
Pull out values without casting:
String str = rec.getString("str");
// => "bar"
Integer integ = rec.getInteger("integ");
// => 5
BigDecimal bigdec = rec.getBigDecimal("bigdec");
// => 1.0
Boolean boole = rec.getBoolean("boole");
// => true
BigDecimal bigdec = rec.getLong("bigdec");
// => 1.0
List<String> = rec.getList("list"); // => [foo, bar]
// => [foo, bar]
Map<String, String> = rec.getMap("map");
// => {}
Get java.util.Optionals instead:
rec.optionalString("str").orElse("baz");
// => "bar"
rec.optionalString("wat").orElse("baz");
// => "baz"
rec.optionalInteger("wat").orElseThrow(() => new RuntimeException("wat"));
// => RuntimeException: wat
Here are all the access methods available:
| Class | Value | java.util.Optional |
|---|---|---|
| java.lang.String | getString | optionalString |
| java.lang.Boolean | getBoolean | optionalBoolean |
| java.lang.Integer | getInteger | optionalInteger |
| java.lang.Long | getLong | optionalLong |
| java.lang.Float | getFloat | optionalFloat |
| java.lang.Double | getDouble | optionalDouble |
| java.math.BigDecimal | getBigDecimal | optionalBigDecimal |
| java.util.Date | getDate | optionalDate |
| java.util.List | getList | optionalList |
| java.util.Map | getMap | optionalMap |
| fun.mike.Record | getRecord | optionalRecord |
A fun.mike.record.TypeMismatchException is thrown when the present value doesn't match the expected type:
Integer str = rec.getInteger("str");
=> fun.mike.record.TypeMismatchException: Value "foo" of class "java.lang.String" for key "str" must be an integer.
Records extend java.util.LinkedHashMap<String, Object>:
Object str = rec.get("str");
// => "bar"
Object str = rec.get("wat");
// => null
So they're mutable:
Record rec = Record.of("a", 1, "b", 2, "c", 3);
// => {a=1, b=2, c=3}
rec.put("d", "3");
// => {a=1, b=2, c=3, d=4}
rec
// => {a=1, b=2, c=3, d=4}
But you can use assoc, dissoc, and select to avoid mutation:
Record rec = Record.of("a", 1, "b", 2, "c", 3);
// => {a=1, b=2, c=3}
Record withD = rec.assoc("d", 4);
// => {a=1, b=2, c=3, d=4}
Record withoutA = rec.dissoc("a");
// => {b=2, c=3}
Record aAndB = rec.select("a", "b");
// => {a=1, b=2}
rec
// => {a=1, b=2, c=3}
Or use set to do a lot of mutation at once:
Record rec = Record.of("a", 1, "b", 2, "c", 3);
// => {a=1, b=2, c=3}
rec.set("b", 3, "c", 4, "d", 5, "e", 6);
// => {a=1, b=3, c=4, d=5, e=6}
rec
// => {a=1, b=3, c=4, d=5, e=6}
Build
Copyright and License
The use and distribution terms for this software are covered by the Eclipse Public License 1.0 which can be found in the file epl-v10.html at the root of this distribution. By using this softwaer in any fashion, you are agreeing to be bound by the terms of this license. You must not remove this notice, or any other, from this software.