Example usage for com.amazonaws.services.dynamodbv2.document.utils ValueMap with

List of usage examples for com.amazonaws.services.dynamodbv2.document.utils ValueMap with

Introduction

In this page you can find the example usage for com.amazonaws.services.dynamodbv2.document.utils ValueMap with.

Prototype

public ValueMap with(String key, Object val) 

Source Link

Document

Sets the value of the specified key to the given value.

Usage

From source file:com.clicktravel.infrastructure.persistence.aws.dynamodb.DynamoDocumentStoreTemplate.java

License:Apache License

private <T extends Item> ScanSpec generateScanSpec(final AttributeQuery query, final Class<T> tableItemType)
        throws InstantiationException, IllegalAccessException, IllegalArgumentException,
        InvocationTargetException, NoSuchMethodException, SecurityException {
    final Class<?> clazz = getScanSpecOperandType(query.getAttributeName(), tableItemType);

    ScanSpec scanSpec = new ScanSpec();

    final StringBuilder filterExpression = new StringBuilder();
    final ValueMap valueMap = new ValueMap();
    int valueMapCount = 0;

    if (query.getCondition().getComparisonOperator() == Operators.NULL) {
        filterExpression.append("attribute_not_exists(").append(query.getAttributeName()).append(")");
    } else if (query.getCondition().getComparisonOperator() == Operators.NOT_NULL) {
        filterExpression.append("attribute_exists(").append(query.getAttributeName()).append(")");
    } else {/*  w ww. j  a v  a 2 s .  c  o m*/
        if (query.getCondition().getComparisonOperator() == Operators.EQUALS) {
            filterExpression.append(query.getAttributeName()).append(" IN (");

            final Iterator<String> valueIterator = query.getCondition().getValues().iterator();
            while (valueIterator.hasNext()) {
                filterExpression.append(":").append(valueMapCount);
                valueMap.with(":" + valueMapCount, valueIterator.next());
                valueMapCount++;
                if (valueIterator.hasNext()) {
                    filterExpression.append(",");
                }
            }
            filterExpression.append(")");
        } else if (query.getCondition().getComparisonOperator() == Operators.LESS_THAN_OR_EQUALS) {
            if (query.getCondition().getValues().size() == 1) {
                filterExpression.append(query.getAttributeName()).append(" <= ").append(":")
                        .append(valueMapCount);
                final Object valueInstance = clazz.getConstructor(String.class)
                        .newInstance(query.getCondition().getValues().iterator().next());
                valueMap.with(":" + valueMapCount, valueInstance);
                valueMapCount++;
            } else {
                // throw exeption??
            }
        } else if (query.getCondition().getComparisonOperator() == Operators.GREATER_THAN_OR_EQUALS) {
            if (query.getCondition().getValues().size() == 1) {
                filterExpression.append(query.getAttributeName()).append(" >= ").append(":")
                        .append(valueMapCount);
                final Object valueInstance = clazz.getConstructor(String.class)
                        .newInstance(query.getCondition().getValues().iterator().next());
                valueMap.with(":" + valueMapCount, valueInstance);
                valueMapCount++;
            } else {
                // throw exeption??
            }
        }
    }

    if (filterExpression.length() > 0) {
        scanSpec = scanSpec.withFilterExpression(filterExpression.toString());
    }
    if (valueMap.size() > 0) {
        scanSpec = scanSpec.withValueMap(valueMap);
    }
    return scanSpec;
}