Rework to be AutoCloseableSupplier instead

Author: jasmith-hs

src/main/java/com/hubspot/jinjava/interpret/AutoCloseableSupplier.java

@@ -0,0 +1,67 @@
+package com.hubspot.jinjava.interpret;
+
+import com.hubspot.jinjava.interpret.AutoCloseableSupplier.AutoCloseableImpl;
+import java.util.function.Consumer;
+import java.util.function.Supplier;
+
+public class AutoCloseableSupplier<T> implements Supplier<AutoCloseableImpl<T>> {
+
+  public interface GenericThrowingFunction<T, R, E extends Exception> {
+    R apply(T t) throws E;
+  }
+
+  public static <T> AutoCloseableSupplier<T> of(T t) {
+    return new AutoCloseableSupplier<>(new AutoCloseableImpl<>(t, ignored -> {}));
+  }
+
+  public static <T> AutoCloseableSupplier<T> of(T t, Consumer<T> closeConsumer) {
+    return new AutoCloseableSupplier<>(new AutoCloseableImpl<>(t, closeConsumer));
+  }
+
+  private final AutoCloseableImpl<T> autoCloseableImplWrapper;
+
+  private AutoCloseableSupplier(AutoCloseableImpl<T> autoCloseableImplWrapper) {
+    this.autoCloseableImplWrapper = autoCloseableImplWrapper;
+  }
+
+  @Override
+  public AutoCloseableImpl<T> get() {
+    return autoCloseableImplWrapper;
+  }
+
+  public T dangerouslyGetWithoutClosing() {
+    return autoCloseableImplWrapper.value();
+  }
+
+  public <R, E extends Exception> AutoCloseableSupplier<R> map(
+    GenericThrowingFunction<T, R, E> mapper
+  ) throws E {
+    T t = autoCloseableImplWrapper.value();
+    return new AutoCloseableSupplier<>(
+      new AutoCloseableImpl<>(
+        mapper.apply(t),
+        r -> autoCloseableImplWrapper.closeConsumer.accept(t)
+      )
+    );
+  }
+
+  public static class AutoCloseableImpl<T> implements java.lang.AutoCloseable {
+
+    private final T t;
+    private final Consumer<T> closeConsumer;
+
+    protected AutoCloseableImpl(T t, Consumer<T> closeConsumer) {
+      this.t = t;
+      this.closeConsumer = closeConsumer;
+    }
+
+    public T value() {
+      return t;
+    }
+
+    @Override
+    public void close() {
+      closeConsumer.accept(t);
+    }
+  }
+}