HopeLangEngine (hope-lang 1.2 API)

java.lang.Object
- io.appform.hope.lang.HopeLangEngine

```
public class HopeLangEngine
extends Object
```
Top level accessor for hope. Creation is expensive. Create and reuse.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static class HopeLangEngine.Builder

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`static HopeLangEngine.Builder`	`builder()`	Create a builder for the parser.
`boolean`	`evaluate(Evaluatable rule, com.fasterxml.jackson.databind.JsonNode node)`	Evaluate a hope lang parsed expression
`boolean`	`evaluate(String hopeLangExpression, com.fasterxml.jackson.databind.JsonNode root)`	Evaluates a hope expression using the provided json to return true or false.
`List<Boolean>`	`evaluate(List<Evaluatable> rules, com.fasterxml.jackson.databind.JsonNode node)`
`OptionalInt`	`evaluateFirst(List<Evaluatable> rules, com.fasterxml.jackson.databind.JsonNode node)`
`Evaluatable`	`parse(String hopeLangExpression)`	Parse a hope lang string.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

evaluate
```
public boolean evaluate(String hopeLangExpression,
                        com.fasterxml.jackson.databind.JsonNode root)
```
Evaluates a hope expression using the provided json to return true or false.

Parameters:

hopeLangExpression - A hope language expression

root - The json node to be evaluated

Returns:

true in case of match

parse
```
public Evaluatable parse(String hopeLangExpression)
                  throws HopeExpressionParserError
```
Parse a hope lang string. The resultant parsed rule can be reused for multiple evaluations.

Parameters:

hopeLangExpression - Parse a string

Returns:

An evaluatable expression tree

Throws:

HopeExpressionParserError

evaluate
```
public boolean evaluate(Evaluatable rule,
                        com.fasterxml.jackson.databind.JsonNode node)
```
Evaluate a hope lang parsed expression

Parameters:

rule - Parsed rule

node - JsonNode for which the match rule is to be evaluated

Returns:

true in case of match

evaluate

public List<Boolean> evaluate(List<Evaluatable> rules,
                              com.fasterxml.jackson.databind.JsonNode node)

evaluateFirst

public OptionalInt evaluateFirst(List<Evaluatable> rules,
                                 com.fasterxml.jackson.databind.JsonNode node)

builder
```
public static HopeLangEngine.Builder builder()
```
Create a builder for the parser.

Returns:

An initialized builder.