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Indexes: Converting to JSON and Accessing Metadata

Entities passed to an index can be converted to JSON using AsJson method. There is also a possibility to access metadata for a specified object using MetadataFor method.

AsJson - Converting to JSON

public static class Products_AllProperties extends AbstractIndexCreationTask {
    public static class Result {
        private String query;

        public String getQuery() {
            return query;
        }

        public void setQuery(String query) {
            this.query = query;
        }
    }

    public Products_AllProperties() {
        map = "docs.Products.Select(product => new { " +
            // convert product to JSON and select all properties from it
            "    Query = this.AsJson(product).Select(x => x.Value) " +
            "})";

        // mark 'query' field as analyzed which enables full text search operations
        index("Query", FieldIndexing.SEARCH);;
    }
}

List<Product> results = session
    .query(Products_AllProperties.Result.class, Products_AllProperties.class)
    .whereEquals("Query", "Chocolade")
    .ofType(Product.class)
    .toList();

MetadataFor - Accessing Metadata

public static class Products_WithMetadata extends AbstractIndexCreationTask {
    public static class Result {
        private Date lastModified;

        public Date getLastModified() {
            return lastModified;
        }

        public void setLastModified(Date lastModified) {
            this.lastModified = lastModified;
        }
    }

    public Products_WithMetadata() {
        map = "docs.Products.Select(product => new { " +
            "    Product = Product, " +
            "    Metadata = this.MetadataFor(product) " +
            "}).Select(this0 => new { " +
            "    LastModified = this0.metadata.Value<DateTime>(\"Last-Modified\") " +
            "})";
    }
}

List<Product> results = session
    .query(Products_WithMetadata.Result.class, Products_WithMetadata.class)
    .orderByDescending("LastModified")
    .ofType(Product.class)
    .toList();