无法加载累加约束，导致约束失败

Question

我一直在尝试在累加的自定义约束工作。我通过实现org.apache.accumulo.core.constraints.Constraint .

创建了约束。

但是当它应用到表时，我得到以下错误

约束失败:ConstraintViolationSummary(constrainClass:org.apache.accumulo.tserver.constraints)。unsatisableconstraint,violationCode:-1,violationDescription:加载约束失败，不接受突变。, numberOfViolatingMutations: 1)

下面是我的代码片段

 package samplepackageforconstraints;
    import java.util.ArrayList;
    import java.util.Collection;
    import java.util.List;
    import org.apache.accumulo.core.constraints.Constraint;
    import org.apache.accumulo.core.data.ColumnUpdate;
    import org.apache.accumulo.core.data.Mutation;
public class LengthConstraintsTest implements Constraint{
    private static final short NOT_ENOUGH_LENGTH = 1;
    @Override
    public List<Short> check(Environment env, Mutation mutation) {
        List<Short> violations = null;
        Collection<ColumnUpdate> updates = mutation.getUpdates();
        for (ColumnUpdate columnUpdate : updates) {
            if (!isLessThanThree(columnUpdate.getValue()))
                violations = addViolation(violations, NOT_ENOUGH_LENGTH);
        }
        return violations;
    }
    @Override
    public String getViolationDescription(short violationCode) {
         switch (violationCode) {
          case NOT_ENOUGH_LENGTH:
            return "Value should be more than 3 character";
        }
        return null;
    }
    private List<Short> addViolation(List<Short> violations, short violation) {
        if (violations == null) {
            violations = new ArrayList<Short>();
            violations.add(violation);
        } else if (!violations.contains(violation)) {
            violations.add(violation);
        }
        return violations;
    }
    private boolean isLessThanThree(byte[] value) {
        if(value.length <3)
        return false;
        else
            return true;
    }
}

我遵循了蓄电池1.7版用户手册中给出的步骤还有用于加载约束

的cloudera

我使用的是版本:1.6.0-cdh5.1.4的accumulo

提前感谢:)

Answer 1

当不能加载约束时，这意味着从类路径加载类存在问题(通常)，或者(不太可能)类不对应于Constraint接口。

您需要将包含自定义约束的jar添加到每个tablet服务器的类路径中。