Examples with JexlException org.apache.commons.jexl2.JexlException used on opensource projects

Example 1 with JexlException

use of org.apache.commons.jexl2.JexlException in project opennms by OpenNMS.

the class JEXLExpressionEngine method applyExpressions.

/**
 * {@inheritDoc}
 */
@Override
public void applyExpressions(final QueryRequest request, final FetchResults results) throws ExpressionException {
    Preconditions.checkNotNull(request, "request argument");
    Preconditions.checkNotNull(results, "results argument");
    final int numExpressions = request.getExpressions().size();
    // Don't do anything if there are no expressions
    if (numExpressions < 1) {
        return;
    }
    // Use to keep track of transient expression so that we don't
    // allocate memory to store their results
    int numNonTransientExpression = 0;
    boolean[] transientFlags = new boolean[numExpressions];
    // Compile the expressions
    int j, k = 0;
    final LinkedHashMap<String, org.apache.commons.jexl2.Expression> expressions = Maps.newLinkedHashMap();
    for (final Expression e : request.getExpressions()) {
        // Populate the transientFlags array
        transientFlags[k] = e.getTransient();
        if (!transientFlags[k]) {
            numNonTransientExpression++;
        }
        k++;
        try {
            expressions.put(e.getLabel(), jexl.createExpression(e.getExpression()));
        } catch (JexlException ex) {
            throw new ExpressionException(ex, "Failed to parse expression label '{}'.", e.getLabel());
        }
    }
    // Prepare the JEXL context
    final Map<String, Object> jexlValues = Maps.newHashMap();
    final JexlContext context = new MapContext(jexlValues);
    // Add constants (i.e. values from strings.properties) retrieved by the fetch operation
    jexlValues.putAll(results.getConstants());
    LOG.debug("JEXL context constants: {}", jexlValues);
    // Add some additional constants for ease of use
    jexlValues.put("__inf", Double.POSITIVE_INFINITY);
    jexlValues.put("__neg_inf", Double.NEGATIVE_INFINITY);
    jexlValues.put("NaN", Double.NaN);
    jexlValues.put("__E", java.lang.Math.E);
    jexlValues.put("__PI", java.lang.Math.PI);
    // Add JexlEvaluateFunctions with current context and jexl engine to allow string constants to be evaluated.
    JexlEvaluateFunctions jexlEvaluateFunctions = new JexlEvaluateFunctions(context, jexl);
    jexl.getFunctions().put("jexl", jexlEvaluateFunctions);
    final long[] timestamps = results.getTimestamps();
    final Map<String, double[]> columns = results.getColumns();
    final int numRows = timestamps.length;
    // Calculate the time span
    jexlValues.put("__diff_time", numRows < 1 ? 0d : timestamps[numRows - 1] - timestamps[0]);
    final double[][] expressionValues = new double[numNonTransientExpression][numRows];
    // Iterate through all of the rows, apply the expressions
    for (int i = 0; i < numRows; i++) {
        // Evaluate every expression, in the same order as which they appeared in the query
        j = k = 0;
        for (final Map.Entry<String, org.apache.commons.jexl2.Expression> expressionEntry : expressions.entrySet()) {
            // Update the timestamp
            jexlValues.put("timestamp", timestamps[i]);
            // add index as a referenced variable in context
            jexlValues.put("__i", Integer.valueOf(i));
            // overwriting values from the last loop
            for (final String sourceLabel : columns.keySet()) {
                jexlValues.put(sourceLabel, columns.get(sourceLabel)[i]);
                // add reference to complete array for each column to allow backwards referencing of samples
                jexlValues.put("__" + sourceLabel, columns.get(sourceLabel));
            }
            // Evaluate the expression
            try {
                Object derived = expressionEntry.getValue().evaluate(context);
                double derivedAsDouble = Utils.toDouble(derived);
                // Only store the values for non-transient expressions
                if (!transientFlags[j++]) {
                    expressionValues[k++][i] = derivedAsDouble;
                }
                // Store the result back in the context, so that it can be referenced
                // by subsequent expression in the row
                jexlValues.put(expressionEntry.getKey(), derivedAsDouble);
            } catch (NullPointerException | NumberFormatException e) {
                throw new ExpressionException(e, "The return value from expression with label '" + expressionEntry.getKey() + "' could not be cast to a Double.");
            } catch (JexlException e) {
                throw new ExpressionException(e, "Failed to evaluate expression with label '" + expressionEntry.getKey() + "'.");
            }
        }
    }
    // Store the results
    j = k = 0;
    for (final String expressionLabel : expressions.keySet()) {
        if (!transientFlags[j++]) {
            columns.put(expressionLabel, expressionValues[k++]);
        }
    }
}

Example 2 with JexlException

use of org.apache.commons.jexl2.JexlException in project traccar by tananaev.

the class ComputedAttributesHandler method handlePosition.

@Override
protected Position handlePosition(Position position) {
    Collection<Attribute> attributes = Context.getAttributesManager().getItems(Context.getAttributesManager().getAllDeviceItems(position.getDeviceId()));
    for (Attribute attribute : attributes) {
        if (attribute.getAttribute() != null) {
            Object result = null;
            try {
                result = computeAttribute(attribute, position);
            } catch (JexlException error) {
                Log.warning(error);
            }
            if (result != null) {
                try {
                    switch(attribute.getType()) {
                        case "number":
                            Number numberValue = (Number) result;
                            position.getAttributes().put(attribute.getAttribute(), numberValue);
                            break;
                        case "boolean":
                            Boolean booleanValue = (Boolean) result;
                            position.getAttributes().put(attribute.getAttribute(), booleanValue);
                            break;
                        default:
                            position.getAttributes().put(attribute.getAttribute(), result.toString());
                    }
                } catch (ClassCastException error) {
                    Log.warning(error);
                }
            }
        }
    }
    return position;
}

Example 3 with JexlException

use of org.apache.commons.jexl2.JexlException in project traccar by traccar.

the class ComputedAttributesHandler method handlePosition.

@Override
protected Position handlePosition(Position position) {
    Collection<Attribute> attributes = Context.getAttributesManager().getItems(Context.getAttributesManager().getAllDeviceItems(position.getDeviceId()));
    for (Attribute attribute : attributes) {
        if (attribute.getAttribute() != null) {
            Object result = null;
            try {
                result = computeAttribute(attribute, position);
            } catch (JexlException error) {
                Log.warning(error);
            }
            if (result != null) {
                try {
                    switch(attribute.getType()) {
                        case "number":
                            Number numberValue = (Number) result;
                            position.getAttributes().put(attribute.getAttribute(), numberValue);
                            break;
                        case "boolean":
                            Boolean booleanValue = (Boolean) result;
                            position.getAttributes().put(attribute.getAttribute(), booleanValue);
                            break;
                        default:
                            position.getAttributes().put(attribute.getAttribute(), result.toString());
                    }
                } catch (ClassCastException error) {
                    Log.warning(error);
                }
            }
        }
    }
    return position;
}

Example 4 with JexlException

use of org.apache.commons.jexl2.JexlException in project javautils by jiadongpo.

the class PropsUtils method resolveVariableExpression.

/**
 * Function that looks for expressions to parse. It parses backwards to capture embedded
 * expressions
 */
private static String resolveVariableExpression(final String value, final int last, final JexlEngine jexl) {
    final int lastIndex = value.lastIndexOf("$(", last);
    if (lastIndex == -1) {
        return value;
    }
    // Want to check that everything is well formed, and that
    // we properly capture $( ...(...)...).
    int bracketCount = 0;
    int nextClosed = lastIndex + 2;
    for (; nextClosed < value.length(); ++nextClosed) {
        if (value.charAt(nextClosed) == '(') {
            bracketCount++;
        } else if (value.charAt(nextClosed) == ')') {
            bracketCount--;
            if (bracketCount == -1) {
                break;
            }
        }
    }
    if (nextClosed == value.length()) {
        throw new IllegalArgumentException("Expression " + value + " not well formed.");
    }
    final String innerExpression = value.substring(lastIndex + 2, nextClosed);
    Object result = null;
    try {
        final Expression e = jexl.createExpression(innerExpression);
        result = e.evaluate(new MapContext());
    } catch (final JexlException e) {
        throw new IllegalArgumentException("Expression " + value + " not well formed. " + e.getMessage(), e);
    }
    if (result == null) {
        // for backward compatibility it is best to return value
        return value;
    }
    final String newValue = value.substring(0, lastIndex) + result.toString() + value.substring(nextClosed + 1);
    return resolveVariableExpression(newValue, lastIndex, jexl);
}

Example 5 with JexlException

use of org.apache.commons.jexl2.JexlException in project jmxtrans by jmxtrans.

the class JexlNamingStrategy method formatName.

/**
 * Format the name for the given result.
 *
 * @param result - the result of a JMX query.
 * @return String - the formatted string resulting from the expression, or null if the formatting fails.
 */
@Override
public String formatName(Result result) {
    String formatted;
    JexlContext context = new MapContext();
    this.populateContext(context, result);
    try {
        formatted = (String) this.parsedExpr.evaluate(context);
    } catch (JexlException jexlExc) {
        LOG.error("error applying JEXL expression to query results", jexlExc);
        formatted = null;
    }
    return formatted;
}