Core Concepts

DevExtremeLoadOptions

Represents a client query with the following key properties:


public class DevExtremeLoadOptions {
    private Integer skip;              // Pagination offset
    private Integer take;              // Number of records to return
    private Boolean requireTotalCount; // Include total count in result
    private Object filter;             // Filter expression (nested arrays)
    private List<SortInfo> sort;       // Sort columns and directions
    private List<GroupInfo> group;     // Group by columns
    private List<SummaryInfo> totalSummary;  // Total aggregations
    private List<SummaryInfo> groupSummary;  // Group aggregations
    private Boolean isLoadingAll;      // Export mode (ignore pagination)
}

Filter Expressions

Filters are JSON arrays with the format: [field, operator, value]

Simple Filter


["firstName", "contains", "John"]

Complex Filter (AND)


[
  ["firstName", "contains", "John"],
  "and",
  ["salary", ">=", 50000]
]

Complex Filter (OR and Nesting)


[
  [
    ["firstName", "=", "John"],
    "or",
    ["firstName", "=", "Jane"]
  ],
  "and",
  ["active", "=", true]
]

Supported Filter Operators

Operator	Description	Example
`=`, `equals`	Equal to	`["status", "=", "active"]`
`<>`	Not equal to	`["status", "<>", "deleted"]`
`>`, `greater`	Greater than	`["age", ">", 18]`
`>=`	Greater than or equal	`["age", ">=", 21]`
`<`, `lower`	Less than	`["price", "<", 100]`
`<=`	Less than or equal	`["price", "<=", 50]`
`contains`	Contains substring (case-insensitive)	`["name", "contains", "john"]`
`notcontains`	Does not contain	`["name", "notcontains", "test"]`
`startswith`	Starts with	`["email", "startswith", "admin"]`
`endswith`	Ends with	`["email", "endswith", ".com"]`
`between`	Between two values	`["age", "between", [18, 65]]`
`null`, `nu`	Is null	`["deletedAt", "null", null]`
`notnull`, `nn`	Is not null	`["email", "notnull", null]`

Special Filter Cases

Null Value Handling


["deletedAt", "=", null]

Generates: deleted_at IS NULL

Field-to-Field Comparison


["actualPrice", ">=", "expectedPrice"]

Generates: actual_price >= expected_price

Date Interval Filtering


["hireDate.Year", "=", 2024]

Generates: EXTRACT(YEAR FROM hire_date) = 2024

Connection Management Modes

DataSource Mode (Recommended for Production)


GridDataProvider gridDataProvider = new GridDataProvider(dataSource);
// Library manages connection lifecycle
// Connections automatically closed after each query
// Thread-safe for read operations
// Best for web applications with connection pooling

Connection Mode (Manual Control)


try (Connection conn = dataSource.getConnection()) {
    GridDataProvider gridDataProvider = new GridDataProvider(conn);
    // Execute multiple queries on same connection
    // Caller responsible for closing connection
    // NOT thread-safe
    // Useful for batch operations or transactions
}